GitHubCI,Frontend.Console: swap .net6 with .net8

This is to fix this compiler error when building in Release
mode:

```
Determining projects to restore...
/usr/share/dotnet/sdk/10.0.100/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.EolTargetFrameworks.targets(32,5): error NETSDK1138: The target framework 'net6.0' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy. [/home/runner/work/geewallet/geewallet/src/GWallet.Frontend.Console/GWallet.Frontend.Console.fsproj]
```

Author: knocte

.github/workflows/CI.yml

@@ -9,23 +9,25 @@ on:
   schedule:
     - cron: "0 0 * * *"
 
+env:
+  DOTNET_VERSION: '8.0'
 
 # FIXME: figure out why we need to clean after make if we
 # want 'make strict' target to really happen without
 # assuming the binaries from previous build are good
 # (msbuild bug?)
 
 jobs:
-  macOS--dotnet6-and-mono:
+  macOS--dotnet-and-mono:
     runs-on: macOS-13
     steps:
     - uses: actions/checkout@v1
       with:
         submodules: false
-    - name: Setup .NET SDK 6.0.x
-      uses: actions/setup-dotnet@v1.7.2
+    - name: Setup .NET SDK
+      uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: '6.0.113'
+        dotnet-version: ${{ env.DOTNET_VERSION }}
     - name: Install specific Xamarin.iOS and Xamarin.Android versions
       run: |
         wget https://download.visualstudio.microsoft.com/download/pr/81c41aaa-a3d7-4875-8416-d04b472379b7/21d9f6c5ad3a6bc2479b2ec4b0685b6c/xamarin.ios-16.0.0.72.pkg
@@ -94,16 +96,16 @@ jobs:
     - name: integration tests
       run: make update-servers
 
-  macOS--dotnet6-only:
+  macOS--dotnet-only:
     runs-on: macOS-13
     steps:
     - uses: actions/checkout@v1
       with:
         submodules: false
-    - name: Setup .NET SDK 6.0.x
-      uses: actions/setup-dotnet@v1.7.2
+    - name: Setup .NET SDK
+      uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: '6.0.113'        
+        dotnet-version: ${{ env.DOTNET_VERSION }}        
     - name: HACK to emulate mono uninstall
       run: sudo rm -f `which mono` && sudo rm -f `which msbuild`
     - name: configure
@@ -121,16 +123,16 @@ jobs:
     - name: integration tests
       run: make update-servers
 
-  windows--dotnet6-and-legacyFramework:
+  windows--dotnet-and-legacyFramework:
     runs-on: windows-latest
     steps:
     - uses: actions/checkout@v1
       with:
         submodules: false
-    - name: Setup .NET SDK 6.0.x
-      uses: actions/setup-dotnet@v1.7.2
+    - name: Setup .NET SDK
+      uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: '6.0.113'
+        dotnet-version: ${{ env.DOTNET_VERSION }}
     - name: configure
       run: .\configure.bat
     - name: build in DEBUG mode
@@ -178,16 +180,16 @@ jobs:
     - name: integration tests
       run: .\make update-servers
 
-  windows--dotnet6-only:
+  windows--dotnet-only:
     runs-on: windows-latest
     steps:
     - uses: actions/checkout@v1
       with:
         submodules: false
-    - name: Setup .NET SDK 6.0.x
-      uses: actions/setup-dotnet@v1.7.2
+    - name: Setup .NET SDK
+      uses: actions/setup-dotnet@v5
       with:
-        dotnet-version: '6.0.113'
+        dotnet-version: ${{ env.DOTNET_VERSION }}
     - name: HACK to emulate legacy .NETFramework uninstall
       run: del $(& "${Env:ProgramFiles(x86)}\Microsoft Visual Studio\Installer\vswhere.exe" -find MSBuild\\**\\Bin\\MSBuild.exe)
     - name: configure
@@ -302,7 +304,7 @@ jobs:
     - name: integration tests
       run: make update-servers
 
-  linux24-vanilla--stockdotnet6-only:
+  linux24-vanilla--stockdotnet-only:
     runs-on: ubuntu-24.04
     container:
       image: "ubuntu:24.04"
@@ -315,7 +317,7 @@ jobs:
     - name: install sudo
       run: apt update && apt install --yes sudo
     - name: install all dependencies
-      run: sudo DEBIAN_FRONTEND=noninteractive apt install --yes git make curl dotnet6
+      run: sudo DEBIAN_FRONTEND=noninteractive apt install --yes git make curl dotnet8
 
     # workaround for https://github.com/actions/runner/issues/2033
     - name: ownership workaround
@@ -344,7 +346,7 @@ jobs:
 
         find . -type f -name "*.fsx" | xargs -t -I {} dotnet fsxc {}
 
-  linux24-vanilla--stockdotnet6-and-newmono:
+  linux24-vanilla--stockdotnet-and-newmono:
     runs-on: ubuntu-24.04
     container:
       image: "ubuntu:24.04"
@@ -357,7 +359,7 @@ jobs:
     - name: install sudo
       run: apt update && apt install --yes sudo
     - name: install all dependencies
-      run: sudo DEBIAN_FRONTEND=noninteractive apt install --yes git make curl dotnet6
+      run: sudo DEBIAN_FRONTEND=noninteractive apt install --yes git make curl dotnet8
     - name: install last version of mono (Microsoft APT repositories)
       run: sudo ./scripts/install_mono_from_microsoft_deb_packages.sh
 
@@ -388,7 +390,7 @@ jobs:
 
         find . -type f -name "*.fsx" | xargs -t -I {} dotnet fsxc {}
 
-  linux24-vanilla--stockdotnet6-and-stockmono:
+  linux24-vanilla--stockdotnet-and-stockmono:
     runs-on: ubuntu-24.04
     container:
       image: "ubuntu:24.04"
@@ -401,7 +403,7 @@ jobs:
     - name: install sudo
       run: apt update && apt install --yes sudo
     - name: install all dependencies
-      run: sudo DEBIAN_FRONTEND=noninteractive apt install --yes git make curl dotnet6 mono-xbuild
+      run: sudo DEBIAN_FRONTEND=noninteractive apt install --yes git make curl dotnet8 mono-xbuild
 
     # workaround for https://github.com/actions/runner/issues/2033
     - name: ownership workaround
@@ -602,19 +604,19 @@ jobs:
     - linux24-github--dotnet-and-newmono
     - linux24-vanilla--stockmono-only
     - linux24-vanilla--newmono-only
-    - linux24-vanilla--stockdotnet6-only
-    - linux24-vanilla--stockdotnet6-and-stockmono
-    - linux24-vanilla--stockdotnet6-and-newmono
+    - linux24-vanilla--stockdotnet-only
+    - linux24-vanilla--stockdotnet-and-stockmono
+    - linux24-vanilla--stockdotnet-and-newmono
     - linux22-github--dotnet-and-mono
     - linux22-github--dotnet-and-newmono
     - linux22-vanilla--stockmono-only
     - linux22-vanilla--newmono-only
-    - windows--dotnet6-and-legacyFramework
+    - windows--dotnet-and-legacyFramework
     - windows--legacyFramework-only
-    - windows--dotnet6-only
-    - macOS--dotnet6-and-mono
+    - windows--dotnet-only
+    - macOS--dotnet-and-mono
     - macOS--mono-only
-    - macOS--dotnet6-only
+    - macOS--dotnet-only
 
     steps:
     - uses: actions/checkout@v1

scripts/make.fsx

@@ -34,6 +34,9 @@ let UNIX_NAME = "gwallet"
 let DEFAULT_FRONTEND = "GWallet.Frontend.Console"
 let BACKEND = "GWallet.Backend"
 
+// format: X.Y (can't be X.Y.Z here
+let DOTNET_VERSION = "8.0"
+
 type BinaryConfig =
     | Debug
     | Release
@@ -270,7 +273,8 @@ let GetPathToFrontendBinariesDir (binaryConfig: BinaryConfig) =
 #if LEGACY_FRAMEWORK
     Path.Combine (FsxHelper.RootDir.FullName, "src", DEFAULT_FRONTEND, "bin", binaryConfig.ToString())
 #else
-    Path.Combine (FsxHelper.RootDir.FullName, "src", DEFAULT_FRONTEND, "bin", binaryConfig.ToString(), "net6.0")
+    Path.Combine (FsxHelper.RootDir.FullName, "src", DEFAULT_FRONTEND, "bin", binaryConfig.ToString(), 
+                  sprintf "net%s" DOTNET_VERSION)
 #endif
 
 let GetPathToBackend () =

src/GWallet.Frontend.Console/GWallet.Frontend.Console.fsproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net8.0</TargetFramework>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="..\GWallet.Backend\Properties\CommonAssemblyInfo.fs">