$ git clone -n https://src.fedoraproject.org/rpms/falkon.git /var/lib/mock/f45-build-8652-393/root/chroot_tmpdir/scmroot/falkon
Cloning into '/var/lib/mock/f45-build-8652-393/root/chroot_tmpdir/scmroot/falkon'...
$ git fetch origin 108072c6c43f3b581f767960fed10bd2bf2a9ae5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/falkon
 * [new ref]         108072c6c43f3b581f767960fed10bd2bf2a9ae5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 108072c 26.08.0