for-each-repo: work correctly in a worktree #26707

Job	Run time
config	9s
fuzz smoke test	1m 25s
rust-analysis	2m 23s
documentation	7m 48s
win+Meson build	5m 58s
sparse	3m 27s
static-analysis	5m 35s
osx-clang (macos-14)	22m 28s
osx-meson (macos-14)	21m 39s
osx-gcc (macos-14)	22m 43s
win build	4m 44s
debian-11 (debian:11)	11m 24s
osx-reftable (macos-14)	19m 56s
win+VS build	0s
linux-musl-meson (alpine:latest)	9m 0s
fedora-breaking-changes-meson (fedora:latest)	10m 47s
linux-meson (ubuntu:rolling)	16m 7s
linux-breaking-changes (ubuntu:rolling)	15m 37s
linux-reftable (ubuntu:rolling)	14m 38s
linux32 (i386/ubuntu:focal)	8m 45s
linux-leaks (ubuntu:rolling)	25m 46s
linux-sha256 (ubuntu:rolling)	14m 37s
linux-asan-ubsan (ubuntu:rolling)	37m 50s
linux-reftable-leaks (ubuntu:rolling)	29m 13s
win+VS test	0s
linux-TEST-vars (ubuntu:20.04)	11m 14s
almalinux-8 (almalinux:8)	9m 7s
win+Meson test (1)	8m 58s
win+Meson test (5)	10m 45s
win+Meson test (6)	8m 4s
win+Meson test (8)	7m 32s
win+Meson test (7)	9m 4s
win+Meson test (0)	6m 19s
win+Meson test (2)	12m 45s
win+Meson test (9)	6m 24s
win+Meson test (4)	9m 53s
win+Meson test (3)	10m 20s
win test (0)	6m 21s
win test (1)	6m 35s
win test (7)	6m 50s
win test (5)	7m 7s
win test (2)	10m 34s
win test (6)	6m 46s
win test (8)	6m 53s
win test (9)	11m 14s
win test (3)	6m 28s
win test (4)	10m 53s
	8h 22m 5s

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