chore: Prep for 4.6.0 (#5263)

### Description
* Update version numbers
* Rebuild standard library doo files (since they record the current
version, and Dafny won't load them unless the version numbers match)
* NOT bothering this time to switch nightly prereleases to be from the
4.6 branch, since it's almost identical to master and I'm going to
cherry-pick over all but one change anyway.

<small>By submitting this pull request, I confirm that my contribution
is made under the terms of the [MIT
license](https://github.com/dafny-lang/dafny/blob/master/LICENSE.txt).</small>

Author: robin-aws

Source/DafnyPipeline/DafnyPipeline.csproj

@@ -89,7 +89,7 @@
       <LinkBase>DafnyRuntimeJava</LinkBase>
       <CopyToOutputDirectory>Always</CopyToOutputDirectory>
     </EmbeddedResource>
-    <EmbeddedResource Include="..\DafnyRuntime\DafnyRuntimeJava\build\libs\DafnyRuntime-4.5.0.jar">
+    <EmbeddedResource Include="..\DafnyRuntime\DafnyRuntimeJava\build\libs\DafnyRuntime-4.6.0.jar">
       <LogicalName>DafnyRuntime.jar</LogicalName>
       <Link>DafnyRuntime.jar</Link>
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>

Source/DafnyRuntime/DafnyRuntime.csproj

@@ -26,7 +26,7 @@
     <Folder Include="DafnyRuntimeJava\build\libs" />
   </ItemGroup>
   <PropertyGroup>
-    <DafnyRuntimeJar>DafnyRuntimeJava/build/libs/DafnyRuntime-4.5.0.jar</DafnyRuntimeJar>
+    <DafnyRuntimeJar>DafnyRuntimeJava/build/libs/DafnyRuntime-4.6.0.jar</DafnyRuntimeJar>
   </PropertyGroup>
   <Target Name="BuildDafnyRuntimeJar" AfterTargets="ResolveReferences" BeforeTargets="CoreCompile" Inputs="$(MSBuildProjectFile);@(DafnyRuntimeJavaInputFile)" Outputs="$(DafnyRuntimeJar)">
 

Source/DafnyRuntime/DafnyRuntimeJava/build.gradle

@@ -17,7 +17,7 @@ dependencies {
 }
 
 group = 'org.dafny'
-version = '4.5.0'
+version = '4.6.0'
 sourceCompatibility = '1.8'
 
 java {