Bump Microsoft.NET.Test.Sdk from 16.9.1 to 16.9.4

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 16.9.1 to 16.9.4.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Commits](microsoft/vstest@v16.9.1...v16.9.4)

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

src/FluffySpoon.Extensions.MicrosoftDependencyInjection.Tests/FluffySpoon.Extensions.MicrosoftDependencyInjection.Tests.csproj

@@ -8,7 +8,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="5.0.1" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
     <PackageReference Include="MSTest.TestAdapter" Version="2.2.3" />
     <PackageReference Include="MSTest.TestFramework" Version="2.2.3" />
   </ItemGroup>