"Format PR" CI Workflow fails on PRs that come from forks.

[nicktobey]

(markup for the workflow found here: https://github.com/dolthub/dolt/blob/main/.github/workflows/ci-format-repo.yaml)

The workflow runs actions/checkout@v3 to fetch the ref pointed to by the PR. But if the PR is from a fork, then the ref isn't in the repo and the action fails.

This can be seen in action on this PR: https://github.com/dolthub/dolt/actions/runs/4580694905/workflow?pr=5655

[fulghum]

This would be a nice one to fix. I missed a CI check failure on a contribution a couple weeks ago because I saw the failure and incorrectly assumed it was this CI step that always fails. My fault for going too fast, but easy to miss failures when you're expecting to see one you have to ignore.

[coffeegoddd]

Not sure how to fix this atm. afaict we're kinda plagued by this issue actions/checkout#455 .

Using pull_request_target event enabling "Allow commits from maintainers" still results in failed commits to the pull request fork branch.

[fulghum]

Thanks for looking into this one. Maybe the best we can do right now is only run auto-format and verify-formatting on PRs in the same repo, and for forks, only run verify-formatting? If that's doable, that would still be a nice improvement where the CI check wouldn't always fail for all contributions; if verify-formatting does fail, at least contributors could still take care of it manually and get all their CI checks green.

[coffeegoddd]

good idea, ill work on this

[coffeegoddd]

Think this does the right thing #5782, closing this issue for now.