Bump SonarAnalyzer.CSharp in /singletonclient

Bumps [SonarAnalyzer.CSharp](https://github.com/SonarSource/sonar-dotnet) from 8.25.0.33663 to 9.6.0.74858.
- [Release notes](https://github.com/SonarSource/sonar-dotnet/releases)
- [Commits](SonarSource/sonar-dotnet@8.25.0.33663...9.6.0.74858)

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

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

singletonclient/SingletonClient/SingletonClient.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
@@ -9,7 +9,7 @@
 
   <ItemGroup>
     <PackageReference Include="Newtonsoft.Json" Version="11.0.2" />
-    <PackageReference Include="SonarAnalyzer.CSharp" Version="8.25.0.33663">
+    <PackageReference Include="SonarAnalyzer.CSharp" Version="9.6.0.74858">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>