Downgrade xunit.extensibility.execution

Downgrade xunit.extensibility.execution to 2.4.1 as it was accidentally upgraded as part of 0.5.0 and the change is causing issues for some projects.

Add migration guide (#805)

Add a migration guide for moving from xunit v2 to v3.

Ignore CA1515

Ignore the CA1515 analyser rule added for .NET 9.

Merge pull request #313 from martincostello/custom-timestamp-format

Custom timestamp format

Merge pull request #308 from ClrCoder/main

Added ProviderAliasAttribute to add standard configuration support.

Merge pull request #247 from martincostello/Test-Coverage

Increase test coverage

Merge pull request #235 from martincostello/dependabot/nuget/ReportGe…

…nerator-4.8.12

Merge pull request #216 from martincostello/Update-PDB-Format

Use default PDB type

Merge pull request #15 from martincostello/Update-Analyzers

Update analyzers

Merge pull request #14 from martincostello/Update-Dependencies

Update dependencies