$ git clone -n https://src.fedoraproject.org/rpms/polly.git /var/lib/mock/f40-build-832543-14883/root/chroot_tmpdir/scmroot/polly
Cloning into '/var/lib/mock/f40-build-832543-14883/root/chroot_tmpdir/scmroot/polly'...
$ git fetch origin 1b3d34726a8a0d8fca5fca21a7390cfccd0dc223:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/polly
 * [new ref]         1b3d34726a8a0d8fca5fca21a7390cfccd0dc223 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1b3d347 18.1.6 Release