Merge test related dependency updates (#271)

* Bump xunit from 2.8.0 to 2.8.1

Bumps [xunit](https://github.com/xunit/xunit) from 2.8.0 to 2.8.1.
- [Commits](xunit/xunit@2.8.0...2.8.1)

---
updated-dependencies:
- dependency-name: xunit
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

* Bump Microsoft.NET.Test.Sdk from 17.9.0 to 17.10.0

Bumps [Microsoft.NET.Test.Sdk](https://github.com/microsoft/vstest) from 17.9.0 to 17.10.0.
- [Release notes](https://github.com/microsoft/vstest/releases)
- [Changelog](https://github.com/microsoft/vstest/blob/main/docs/releases.md)
- [Commits](microsoft/vstest@v17.9.0...v17.10.0)

---
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>

* Bump xunit.runner.visualstudio from 2.8.0 to 2.8.1

Bumps [xunit.runner.visualstudio](https://github.com/xunit/visualstudio.xunit) from 2.8.0 to 2.8.1.
- [Release notes](https://github.com/xunit/visualstudio.xunit/releases)
- [Commits](xunit/visualstudio.xunit@2.8.0...2.8.1)

---
updated-dependencies:
- dependency-name: xunit.runner.visualstudio
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

---------

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: AArnott

Directory.Packages.props

@@ -6,9 +6,9 @@
     <CentralPackageTransitivePinningEnabled>true</CentralPackageTransitivePinningEnabled>
   </PropertyGroup>
   <ItemGroup>
-    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.9.0" />
-    <PackageVersion Include="xunit.runner.visualstudio" Version="2.8.0" />
-    <PackageVersion Include="xunit" Version="2.8.0" />
+    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
+    <PackageVersion Include="xunit.runner.visualstudio" Version="2.8.1" />
+    <PackageVersion Include="xunit" Version="2.8.1" />
   </ItemGroup>
   <ItemGroup>
     <GlobalPackageReference Include="CSharpIsNullAnalyzer" Version="0.1.495" />