$ git clone -n https://src.fedoraproject.org/rpms/ghc-io-streams.git /var/lib/mock/f38-build-side-42-init-devel-1065226-29775/root/chroot_tmpdir/scmroot/ghc-io-streams
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1065226-29775/root/chroot_tmpdir/scmroot/ghc-io-streams'...
$ git fetch origin 5d02d251ab861feb4c19687138eb516b5ac2ad9c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-io-streams
 * [new ref]         5d02d251ab861feb4c19687138eb516b5ac2ad9c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5d02d25 Convert to %autorelease and %autochangelog