$ git clone -n https://src.fedoraproject.org/rpms/magic.git /var/lib/mock/f41-build-854312-166838/root/chroot_tmpdir/scmroot/magic
Cloning into '/var/lib/mock/f41-build-854312-166838/root/chroot_tmpdir/scmroot/magic'...
$ git fetch origin 63f23bcc576503ab9ed4650631a1ba83c4c8cd32:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/magic
 * [new ref]         63f23bcc576503ab9ed4650631a1ba83c4c8cd32 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 63f23bc 8.3.491