$ git clone -n https://src.fedoraproject.org/rpms/glpk.git /var/lib/mock/f40-build-739747-109242/root/chroot_tmpdir/scmroot/glpk
Cloning into '/var/lib/mock/f40-build-739747-109242/root/chroot_tmpdir/scmroot/glpk'...
$ git fetch origin b2b36c3833fd0efc8104895f4f50ef444f605111:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/glpk
 * [new ref]         b2b36c3833fd0efc8104895f4f50ef444f605111 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b2b36c3 Add changelog entry for Yaakov's change