win+Meson test failures due to ps/build-meson-fixes-0130 topic?

[Junio C Hamano <gitster@pobox.com>]

As of yesterday, 'next' started failing all the "win+Meson test"
jobs.

https://github.com/git/git/actions/runs/13506034920

I had to do one of my least favourite activities working on Git:
bisecting CI breakage on a platform I have no idea how well it
works.

Here is the full "stack" of changes, it contains all the topics
merged between 'master' and 'next', plus a single change that
butchers .github/workflows/main.yml to leave only three jobs
(ci-config, windows-meson-build, and windows-meson-test).

    3a7e83b527 Merge branch 'ps/build-meson-fixes-0130'
    e59193e984 Merge branch 'ek/mingw-rename-symlink'
    a209cf1427 Merge branch 'po/meson-perl-fix'
    9f1e73677c Merge branch 'ua/os-version-capability'
    82f01cb375 Merge branch 'ms/rename-match-name-with-pattern'
    8b04381049 Merge branch 'ad/set-default-target-in-makefiles'
    2cab1bd7d0 Merge branch 'pw/merge-tree-stdin-deadlock-fix'
    92b43de9df Merge branch 'mh/doc-commit-title-not-subject'
    685c150623 Merge branch 'bc/diff-reject-empty-arg-to-pickaxe'
    c5093fc2d8 Merge branch 'tb/new-make-fix'
    9091607e95 Merge branch 'da/xdiff-w-sign-compare-workaround'
    01e86410fe GitHub CI: trim and slim for win+Meson test breakage hunting
    2d2a71ce85 The thirteenth batch

At 01e86410fe and e59193e984, CI seems to pass.

https://github.com/git/git/actions/runs/13528755524

With ps/build-meson-fixes-0130 at 3a7e83b527, all the "win+Meson
test" jobs fail.  I suspect that the series does not break
individual tests but the breakage is in somewhere more
framework-ish?  I didn't look into individual test job failures.

https://github.com/git/git/actions/runs/13529323827

I'll also note that in one of my earlier attempts (which had
ek/mingw-rename-symlink merged before po/meson-perl-fix), one of the
10 "win+Meson test" jobs failed ("win+Meson test (7)" to be exact).
Rerunning the failed test succeeds, so there must be something flaky
in t0610-reftable-basics test that is exposed by this change,
perhaps?

  https://github.com/git/git/actions/runs/13528071468/attempts/1
  https://github.com/git/git/actions/runs/13528071468/attempts/2

As the ps/build-meson-fixes-0130 topic has 13 changes, and each
iteration in the above exercise took somewhere around 20 minutes, I
won't dive into the topic myself to identify which one of these
individual topics causes the breakage.  This however gave me enough
to go on to today's 'master' integration (mainly, by mark the topic
to be held in 'next' until this gets resolved, and deal with the
other topics).

Thanks.