Merge main into releases/v2

[github-actions]

Merging 66aeadb into releases/v2.

Conductor for this PR is @alexet.

Contains the following pull requests:

• Mergeback v2.2.9 refs/heads/releases/v2 into main #1609 (@henrymercer)
• Follow-up improvements to the diagnostics workaround #1610 (@henrymercer)
• Use new location for external queries #1613 (@aeisenberg)
• Disable flaky Swift autobuild checks #1620 (@henrymercer)
• Remove checks for triggering on specific paths #1625 (@rneatherway)
• Enable diagnostics functionality on GHES #1626 (@henrymercer)
• Update default CodeQL bundle version to 2.12.6 #1629 (@alexet)
• Automate the bundle upgrade #1630 (@henrymercer)
• Skip the SARIF notification object workaround for CLIs that have fixed this bug #1631 (@henrymercer)
• Move to the codeql-testing org #1632 (@aeisenberg)

Please do the following:

• Ensure the CHANGELOG displays the correct version and date.
• Ensure the CHANGELOG includes all relevant, user-facing changes since the last release.
• Check that there are not any unexpected commits being merged into the releases/v2 branch.
• Ensure the docs team is aware of any documentation changes that need to be released.
• Approve and merge this PR. Make sure Create a merge commit is selected rather than Squash and merge or Rebase and merge.
• Merge the mergeback PR that will automatically be created once this PR is merged.