chore(deps): update dependency xunit to v2.6.6 (#10867)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Directory.Packages.props

@@ -85,6 +85,6 @@
     <PackageVersion Include="Xunit.Priority" Version="1.1.6" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="2.5.6" />
     <PackageVersion Include="Xunit.SkippableFact" Version="1.4.13" />
-    <PackageVersion Include="xunit" Version="2.6.5" />
+    <PackageVersion Include="xunit" Version="2.6.6" />
   </ItemGroup>
 </Project>