$ git clone -n https://src.fedoraproject.org/rpms/golang-x-vuln.git /var/lib/mock/f40-build-1873427-25022/root/chroot_tmpdir/scmroot/golang-x-vuln
Cloning into '/var/lib/mock/f40-build-1873427-25022/root/chroot_tmpdir/scmroot/golang-x-vuln'...
$ git fetch origin b4a04b5092f2b140df19cb1a57eef10fbc66b4ff:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-x-vuln
 * [new ref]         b4a04b5092f2b140df19cb1a57eef10fbc66b4ff -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b4a04b5 Fix whitespaces