Bump Microsoft.CSharp, Scriban and System.Threading.Tasks.Extensions

Bumps Microsoft.CSharp, [Scriban](https://github.com/scriban/scriban) and System.Threading.Tasks.Extensions. These dependencies needed to be updated together.

Updates `Microsoft.CSharp` from 4.7.0 to 4.5.0

Updates `Scriban` from 5.10.0 to 5.12.1
- [Release notes](https://github.com/scriban/scriban/releases)
- [Changelog](https://github.com/scriban/scriban/blob/master/changelog.md)
- [Commits](scriban/scriban@5.10.0...5.12.1)

Updates `System.Threading.Tasks.Extensions` from 4.5.4 to 4.5.0

---
updated-dependencies:
- dependency-name: Microsoft.CSharp
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: Scriban
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: System.Threading.Tasks.Extensions
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

src/GraphQL.Server.SourceGenerators/GraphQL.Server.SourceGenerators.csproj

@@ -28,7 +28,7 @@
         <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.11.0" PrivateAssets="all" />
         <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.11.0" PrivateAssets="all" />
         <PackageReference Include="System.Text.Json" Version="8.0.5" PrivateAssets="all" GeneratePathProperty="true" />
-        <PackageReference Include="Scriban" Version="5.10.0" IncludeAssets="Build" />
+        <PackageReference Include="Scriban" Version="5.12.1" IncludeAssets="Build" />
         <PackageReference Include="Microsoft.CSharp" Version="4.7.0" PrivateAssets="all" />
         <PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.4" PrivateAssets="all" />
     </ItemGroup>