$ git clone -n https://src.fedoraproject.org/rpms/mairix.git /var/lib/mock/f40-build-2009965-45541/root/chroot_tmpdir/scmroot/mairix
Cloning into '/var/lib/mock/f40-build-2009965-45541/root/chroot_tmpdir/scmroot/mairix'...
$ git fetch origin a72e15f9f8acf1ed554d6c639b436a5e836d0dc8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mairix
 * [new ref]         a72e15f9f8acf1ed554d6c639b436a5e836d0dc8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a72e15f convert license tag to SPDX