$ git clone -n https://src.fedoraproject.org/rpms/golang-x-mod.git /var/lib/mock/f40-build-1236387-22898/root/chroot_tmpdir/scmroot/golang-x-mod
Cloning into '/var/lib/mock/f40-build-1236387-22898/root/chroot_tmpdir/scmroot/golang-x-mod'...
$ git fetch origin 4d9becc1696ed140b1566554051ad7862d2e8350:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-x-mod
 * [new ref]         4d9becc1696ed140b1566554051ad7862d2e8350 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4d9becc update to v0.18.0, close rhbz#2290650