$ git clone -n https://src.fedoraproject.org/rpms/rubygem-vte.git /var/lib/mock/f40-build-772526-126424/root/chroot_tmpdir/scmroot/rubygem-vte
Cloning into '/var/lib/mock/f40-build-772526-126424/root/chroot_tmpdir/scmroot/rubygem-vte'...
$ git fetch origin 2bcc6b7efbcbf525a95f67c18769fbe5d8d03772:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-vte
 * [new ref]         2bcc6b7efbcbf525a95f67c18769fbe5d8d03772 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2bcc6b7 append changelog