$ git clone -n https://src.fedoraproject.org/rpms/bootc.git /var/lib/mock/f39-build-1572828-37792/root/chroot_tmpdir/scmroot/bootc
Cloning into '/var/lib/mock/f39-build-1572828-37792/root/chroot_tmpdir/scmroot/bootc'...
$ git fetch origin ab5e23251f5abb5d215a46afe8c02dc72d27589d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/bootc
 * [new ref]         ab5e23251f5abb5d215a46afe8c02dc72d27589d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ab5e232 Initial import