$ git clone -n https://src.fedoraproject.org/rpms/magic.git /var/lib/mock/f41-build-846568-163104/root/chroot_tmpdir/scmroot/magic
Cloning into '/var/lib/mock/f41-build-846568-163104/root/chroot_tmpdir/scmroot/magic'...
$ git fetch origin 9e31e36327eb9ecfb81197fe2cb60cb09ad1c72a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/magic
 * [new ref]         9e31e36327eb9ecfb81197fe2cb60cb09ad1c72a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9e31e36 8.3.489