$ git clone -n https://src.fedoraproject.org/rpms/grep.git /var/lib/mock/f42-build-888852-188755/root/chroot_tmpdir/scmroot/grep
Cloning into '/var/lib/mock/f42-build-888852-188755/root/chroot_tmpdir/scmroot/grep'...
$ git fetch origin 1954ef093a197198fdc2d043708cb7b63e0a839a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/grep
 * [new ref]         1954ef093a197198fdc2d043708cb7b63e0a839a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1954ef0 Rebuilt for https://fedoraproject.org/wiki/Fedora_42_Mass_Rebuild