$ git clone -n https://src.fedoraproject.org/rpms/cab.git /var/lib/mock/f39-build-1847528-42152/root/chroot_tmpdir/scmroot/cab
Cloning into '/var/lib/mock/f39-build-1847528-42152/root/chroot_tmpdir/scmroot/cab'...
$ git fetch origin f4b02b953dfe205f04dfa7ba716b670961cd422d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cab
 * [new ref]         f4b02b953dfe205f04dfa7ba716b670961cd422d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f4b02b9 https://hackage.haskell.org/package/cab-0.2.21/changelog