Bump SonarAnalyzer.CSharp from 9.20.0.85982 to 9.21.0.86780

Bumps [SonarAnalyzer.CSharp](https://github.com/SonarSource/sonar-dotnet) from 9.20.0.85982 to 9.21.0.86780.
- [Release notes](https://github.com/SonarSource/sonar-dotnet/releases)
- [Commits](SonarSource/sonar-dotnet@9.20.0.85982...9.21.0.86780)

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

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

Directory.Packages.props

@@ -30,7 +30,7 @@
     <PackageVersion Include="MSTest.TestAdapter" Version="3.2.2" />
     <PackageVersion Include="MSTest.TestFramework" Version="3.2.2" />
     <PackageVersion Include="coverlet.collector" Version="6.0.1" PrivateAssets="all" />
-    <GlobalPackageReference Include="SonarAnalyzer.CSharp" Version="9.20.0.85982" />
+    <GlobalPackageReference Include="SonarAnalyzer.CSharp" Version="9.21.0.86780" />
     <GlobalPackageReference Include="DotNet.ReproducibleBuilds" Version="1.1.1" />
   </ItemGroup>
 </Project>