Bump Microsoft.NET.Test.Sdk from 17.8.0 to 17.9.0 in /src/csharp/Intel

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 17.8.0 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@v17.8.0...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] <support@github.com>

src/csharp/Intel/Iced.UnitTests/Iced.UnitTests.csproj

@@ -14,7 +14,7 @@
   <ItemGroup>
     <PackageReference Include="coverlet.msbuild" Version="6.0.0" />
     <!-- NOTE: when updating this thing, make sure it hasn't gotten slower (it's happened twice now!) -->
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0" />
     <PackageReference Include="xunit" Version="2.6.6" />
     <PackageReference Include="xunit.runner.console" Version="2.6.6" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.5.6" />