github: Only run the checklist checker for PRs against main

[jhb]

Summary

Currently this check is run on every push to stable branches which all
fail since they fail to fetch the non-existent .github/path-rules.txt
from the just-updated branches.

[jhb]

You can check the status of the most recent commit on any stable branch at GitHub.com/freebsd/freebsd-src to see the current failure with an HttpError. This matches style.yaml which only runs for PRs against main.

[jhb]

(Unfortunately there doesn't seem to be an easy way to actually test this short of pushing it and seeing what happens.)

[imp]

would it make sense to MFC the .github/path-rules.txt to 14 and 15?

[jhb]

In D60709#1392523, @imp wrote:

would it make sense to MFC the .github/path-rules.txt to 14 and 15?

Well, we only apply the style check to main as this is intended for external PRs, not really MFCs? I don't know that we want significant external changes to stable branches that don't go through main first?

[jhb]

In D60709#1392630, @jhb wrote:

In D60709#1392523, @imp wrote:

would it make sense to MFC the .github/path-rules.txt to 14 and 15?

Well, we only apply the style check to main as this is intended for external PRs, not really MFCs? I don't know that we want significant external changes to stable branches that don't go through main first?

But also, I think the tricky point is that the hook that exists stable/14 and stable/15 isn't the one running for commits pushed to stable/14 and stable/15, instead the hook that exists in main is being run on every commit pushed by the mirror. That seems really odd and wasteful.

[imp]

In D60709#1392631, @jhb wrote:

In D60709#1392630, @jhb wrote:

In D60709#1392523, @imp wrote:

would it make sense to MFC the .github/path-rules.txt to 14 and 15?

Well, we only apply the style check to main as this is intended for external PRs, not really MFCs? I don't know that we want significant external changes to stable branches that don't go through main first?

But also, I think the tricky point is that the hook that exists stable/14 and stable/15 isn't the one running for commits pushed to stable/14 and stable/15, instead the hook that exists in main is being run on every commit pushed by the mirror. That seems really odd and wasteful.

Yea. That's always been a source of confusion for me, so just running it on main is likely the best bet.