Bump Microsoft.NET.Test.Sdk from 17.3.3 to 17.9.0

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 17.3.3 to 17.9.0.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Changelog](https://github.com/microsoft/vstest/blob/main/docs/releases.md)
- [Commits](microsoft/vstest@v17.3.3...v17.9.0)

---
updated-dependencies:
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Tests.props

@@ -12,7 +12,7 @@
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.3.3" Condition="'$(TargetFramework)' == 'netcoreapp2.1'" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0" Condition="'$(TargetFramework)' == 'netcoreapp2.1'" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" Condition="'$(TargetFramework)' != 'netcoreapp2.1'" />
     <PackageReference Include="Shouldly" Version="4.2.1" />
     <PackageReference Include="xunit" Version="2.6.6" />