Bump the dotnet group (#44257)

Bumps the dotnet group in /docs/azure/sdk/snippets/unit-testing with 2 updates: [xunit](https://github.com/xunit/xunit) and [xunit.runner.visualstudio](https://github.com/xunit/visualstudio.xunit).


Updates `xunit` from 2.9.2 to 2.9.3
- [Commits](xunit/xunit@v2-2.9.2...v2-2.9.3)

Updates `xunit.runner.visualstudio` from 3.0.0 to 3.0.1
- [Release notes](https://github.com/xunit/visualstudio.xunit/releases)
- [Commits](xunit/visualstudio.xunit@3.0.0...3.0.1)

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

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

Author: dependabot[bot]

docs/azure/sdk/snippets/unit-testing/UnitTestingSampleApp.csproj

@@ -15,8 +15,8 @@
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
     <PackageReference Include="Moq" Version="[4.20.72]" /> <!-- Context: https://github.com/Azure/azure-sdk-for-net/issues/38111 -->
     <PackageReference Include="NSubstitute" Version="5.3.0" />
-    <PackageReference Include="xunit" Version="2.9.2" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="3.0.0">
+    <PackageReference Include="xunit" Version="2.9.3" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="3.0.1">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>