$ git clone -n https://src.fedoraproject.org/rpms/python-frozenlist.git /var/lib/mock/f40-build-770896-125901/root/chroot_tmpdir/scmroot/python-frozenlist
Cloning into '/var/lib/mock/f40-build-770896-125901/root/chroot_tmpdir/scmroot/python-frozenlist'...
$ git fetch origin 5c56cdcd4051656db964c95d7025f4f415e7def2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/python-frozenlist
 * [new ref]         5c56cdcd4051656db964c95d7025f4f415e7def2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5c56cdc Update to 1.4.1 (close RHBZ#2254700)