t: allow use of "sed -E" #26880

Job	Run time
config	9s
fuzz smoke test	1m 33s
static-analysis	5m 20s
win build	4m 58s
win+Meson build	5m 39s
win+VS build	0s
sparse	3m 27s
rust-analysis	1m 30s
documentation	7m 36s
osx-reftable (macos-14)	20m 41s
osx-meson (macos-14)	22m 55s
osx-clang (macos-14)	15m 21s
osx-gcc (macos-14)	16m 26s
linux-meson (ubuntu:rolling)	15m 4s
debian-11 (debian:11)	11m 27s
linux-reftable-leaks (ubuntu:rolling)	29m 54s
almalinux-8 (almalinux:8)	8m 31s
linux-asan-ubsan (ubuntu:rolling)	35m 15s
fedora-breaking-changes-meson (fedora:latest)	10m 48s
linux32 (i386/ubuntu:focal)	10m 52s
linux-TEST-vars (ubuntu:20.04)	14m 43s
linux-reftable (ubuntu:rolling)	14m 57s
linux-musl-meson (alpine:latest)	8m 47s
linux-breaking-changes (ubuntu:rolling)	13m 59s
linux-sha256 (ubuntu:rolling)	14m 12s
linux-leaks (ubuntu:rolling)	29m 46s
win+VS test	0s
win+Meson test (2)	31s
win+Meson test (9)	50s
win+Meson test (3)	35s
win+Meson test (7)	32s
win+Meson test (8)	42s
win+Meson test (6)	34s
win+Meson test (5)	33s
win+Meson test (4)	40s
win+Meson test (0)	33s
win+Meson test (1)	40s
win test (2)	8m 35s
win test (0)	8m 28s
win test (3)	8m 12s
win test (1)	6m 10s
win test (4)	9m 31s
win test (5)	7m 35s
win test (9)	9m 55s
win test (8)	5m 58s
win test (6)	6m 30s
win test (7)	7m 23s
	6h 48m 17s

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