t: add greplint.pl and convert grep to test_grep #28243

Job	Run time
config	9s
fuzz smoke test	1m 19s
win build	8m 35s
win+Meson build	8m 35s
documentation	8m 35s
sparse	8m 35s
rust-analysis	8m 35s
osx-clang (macos-14)	8m 35s
osx-reftable (macos-14)	8m 35s
osx-gcc (macos-14)	8m 35s
static-analysis	8m 35s
osx-meson (macos-14)	8m 35s
win+VS build	0s
linux-reftable (ubuntu:rolling)	8m 35s
linux-musl-meson (alpine:latest)	8m 35s
linux32 (i386/ubuntu:focal)	8m 36s
linux-breaking-changes (ubuntu:rolling)	8m 35s
almalinux-8 (almalinux:8)	8m 35s
fedora-breaking-changes-meson (fedora:latest)	8m 36s
linux-leaks (ubuntu:rolling)	8m 35s
debian-11 (debian:11)	8m 35s
linux-TEST-vars (ubuntu:20.04)	8m 36s
linux-asan-ubsan (ubuntu:rolling)	8m 35s
linux-sha256 (ubuntu:rolling)	8m 35s
linux-meson (ubuntu:rolling)	8m 35s
linux-reftable-leaks (ubuntu:rolling)	8m 34s
win+VS test	-1s
win test	-1s
win+Meson test	-1s
	3h 18m 52s

Provide feedback