build(deps): bump xunit from 2.6.4 to 2.6.6 in /integrationtests

Bumps [xunit](https://github.com/xunit/xunit) from 2.6.4 to 2.6.6.
- [Commits](xunit/xunit@2.6.4...2.6.6)

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

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

integrationtests/IntegrationTests.Shared.Tests/IntegrationTests.Shared.Tests.csproj

@@ -9,7 +9,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
-    <PackageReference Include="xunit" Version="2.6.4" />
+    <PackageReference Include="xunit" Version="2.6.6" />
     <PackageReference Include="xunit.runner.console" Version="2.6.4">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>