CSCTTV-3775 Upgrade from .NET 6.0 to .NET 8.0 (#241)

* Upgrade .NET version from 6.0 to 8.0. Upgrade NuGet packages.

* Use NET 8.0 sdk image in Docker build. Delete Rahti1 related OpenShift config

Author: sarkikos

.vscode/launch.json

@@ -10,7 +10,7 @@
             "request": "launch",
             "preLaunchTask": "build",
             "launchSettingsProfile": "http",
-            "program": "${workspaceFolder}/aspnetcore/src/api/bin/Debug/net6.0/api.dll",
+            "program": "${workspaceFolder}/aspnetcore/src/api/bin/Debug/net8.0/api.dll",
             "args": [],
             "cwd": "${workspaceFolder}/aspnetcore/src/api",
             "stopAtEntry": false,

aspnetcore/openshift/api/Dockerfile

@@ -1,5 +1,5 @@
 # Builder
-FROM mcr.microsoft.com/dotnet/sdk:6.0 AS build-env
+FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build-env
 WORKDIR /app
 # Copy csproj and restore as distinct layers
 COPY aspnetcore/custom_nuget/ /app/custom_nuget
@@ -13,7 +13,7 @@ RUN dotnet publish -c Release -o out
 
 
 # Runtime image
-FROM mcr.microsoft.com/dotnet/aspnet:6.0
+FROM mcr.microsoft.com/dotnet/aspnet:8.0
 WORKDIR /app
 COPY --from=build-env /app/out .
 EXPOSE 8080