$ git clone -n https://src.fedoraproject.org/rpms/cosmic-comp.git /var/lib/mock/f45-build-46570-846/root/chroot_tmpdir/scmroot/cosmic-comp
Cloning into '/var/lib/mock/f45-build-46570-846/root/chroot_tmpdir/scmroot/cosmic-comp'...
$ git fetch origin 6ed6c63390cee903b697f114feea90e21fbf29f7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cosmic-comp
 * [new ref]         6ed6c63390cee903b697f114feea90e21fbf29f7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6ed6c63 Update to 1.6.0