Unfreeze the xunit version

[f-alizada]

Context

In the PR: #10484 of retargeting to dotnet 9, in order to reduce amount of changes in one change, we have freezed the xunit version. New version of xunit brings new rules/suggestions/warnings, that would be great to resolve.

Goal

Once the #10484 is merged:

• remove the lines

  msbuild/eng/Versions.props

  Lines 82 to 87 in d9192ec

  	<PropertyGroup>
  	<XUnitVersion>2.4.2</XUnitVersion>
  	<XUnitAnalyzersVersion>1.1.0</XUnitAnalyzersVersion>
  	<XUnitRunnerConsoleVersion>$(XUnitVersion)</XUnitRunnerConsoleVersion>
  	<XUnitRunnerVisualStudioVersion>2.4.3</XUnitRunnerVisualStudioVersion>
  	</PropertyGroup>

• Address the build warnings. After the Manual update dependencies from dotnet/arcade #10577 is merged the new warnings of xunit analyzers were disabled. The goal is to check each warning and enable or leave as it is with explanation
  • Enable/disable xunit2020 rule #10586
  • Enable/disable xUnit1012 rule #10589
  • Enable/disable xUnit2029 rule #10599
  • Enable/disable xUnit1031 rule
  • Enable/disable xUnit2013 rule

[f-alizada]

With updated justifications for disabled rules:
#10641
#10663

The issue could be closed.