nuget: bump Microsoft.CodeAnalysis.CSharp from 4.2.0 to 4.4.0 (#4025)

Bumps [Microsoft.CodeAnalysis.CSharp](https://github.com/dotnet/roslyn) from 4.2.0 to 4.4.0.
- [Release notes](https://github.com/dotnet/roslyn/releases)
- [Changelog](https://github.com/dotnet/roslyn/blob/main/docs/Breaking%20API%20Changes.md)
- [Commits](https://github.com/dotnet/roslyn/compare/v4.2.0...Visual-Studio-2019-Version-16.0-Preview-4.4)

---
updated-dependencies:
- dependency-name: Microsoft.CodeAnalysis.CSharp
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Ryujinx.Horizon.Generators/Ryujinx.Horizon.Generators.csproj

@@ -9,7 +9,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.2.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.4.0" />
   </ItemGroup>
 
 </Project>