Bump xunit from 2.6.5 to 2.6.6

Bumps [xunit](https://github.com/xunit/xunit) from 2.6.5 to 2.6.6.
- [Commits](xunit/xunit@2.6.5...2.6.6)

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

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

Author: dependabot[bot]

src/Microsoft.Graph.Cli.Core.Tests/Microsoft.Graph.Cli.Core.Tests.csproj

@@ -14,7 +14,7 @@
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
     <PackageReference Include="Moq" Version="4.20.70" />
     <PackageReference Include="Spectre.Console.Testing" Version="0.48.0" />
-    <PackageReference Include="xunit" Version="2.6.5" />
+    <PackageReference Include="xunit" Version="2.6.6" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.5.6">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>