FYI: Slim potential for catastrophic bugs in git tag handling in precommit

[Allen Wittenauer <aw...@effectivemachines.com.INVALID>]

	Just an FYI.  Today I worked on tracking down the problems that we've had with GitHub Actions working on a tag (YETUS-966).  I think I've got it licked, but one of the outcomes was that prior to the PR (which is now waiting for review) tag checkout was slightly non-deterministic.  In the _vast_ majority of cases, the CI system + test-patch did the correct thing and operations were done on the tag.  But in some cases, FETCH_HEAD was pointing to something else entirely and the branch compilation was actually being done on some other SHA.  This bug would have only impacted qbt or test-patch --empty-patch on tags in real-world scenarios.

	Anyway, I'm fairly confident https://github.com/apache/yetus/pull/138 will fix the tag situation while mostly maintaining expected behavior in other uses. At least based upon my quick tests on Cirrus CI, Circle CI, and GitHub Actions. Note that this fix will now _overwrite_ any local tags that conflict with remote tags when --resetrepo is configured.