tests/test_ruleset_hint_tracking_branch.py: the "kept at its commit" check cannot catch a new seed commit made in the same second #922

Goal: the end-to-end ruleset-hint test fails when a re-run makes a new seed commit instead of reusing the held one, however fast the run is.

Filed by lane openRepoShape-3, from its triage of #459 at the v1.1.1 release commit 5017830. It groups #459's line U007 (#506's N5), the one pure test gap in the triage that no other group holds, one pull request's worth.

"Kept at its commit" cannot see a same-second commit (U007)

State. tests/test_ruleset_hint_tracking_branch.py:429-432 compares each leg's tip with the first run's (tip(...) == before[repo]), and the second run sets no later committer date.

What happens. A new seed commit made in the same second, with the same tree and identity, is the same object, so with _take_held_seed disabled the [scaffold-code-main] case still passes while five other tests fail. The dedicated reuse test pins a later date (tests/test_scaffold_reuse_seeded_legs.py:161, GIT_COMMITTER_DATE in 2031), so the guard as a whole holds.

Evidence. The lines above at 5017830.

Direction. Give the second run a later GIT_COMMITTER_DATE, so a re-made seed has another id.

Size: S.

Lane: openreposhape-3 (openRepoShape-3)