$ git clone -n https://src.fedoraproject.org/rpms/cosmic-store.git /var/lib/mock/f41-build-side-1-3097280-39322/root/chroot_tmpdir/scmroot/cosmic-store
Cloning into '/var/lib/mock/f41-build-side-1-3097280-39322/root/chroot_tmpdir/scmroot/cosmic-store'...
$ git fetch origin 55d7bc9afc3d6885908be2ab897e42260bbff0d9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cosmic-store
 * [new ref]         55d7bc9afc3d6885908be2ab897e42260bbff0d9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 55d7bc9 "Update to 1.0.0~alpha.3"