build(deps): bump Microsoft.NET.Test.Sdk from 17.2.0 to 17.3.1 in /src

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 17.2.0 to 17.3.1.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Commits](microsoft/vstest@v17.2.0...v17.3.1)

---
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/Directory.build.props

@@ -46,7 +46,7 @@
   </PropertyGroup>
 
   <ItemGroup Condition="$(IsTestProject) or $(MSBuildProjectName.Contains('TestRunner'))">
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.2.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.3.1" />
     <PackageReference Include="xunit" Version="2.4.1" />
     <PackageReference Include="Xunit.StaFact" Version="1.1.11" />
     <PackageReference Include="FluentAssertions" Version="6.7.0" />