$ git clone -n https://src.fedoraproject.org/rpms/ghc-old-time.git /var/lib/mock/f38-build-side-42-init-devel-847295-28422/root/chroot_tmpdir/scmroot/ghc-old-time
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-847295-28422/root/chroot_tmpdir/scmroot/ghc-old-time'...
$ git fetch origin 8ba3df7235b76e045ad2a6a00bf2a519280ea9ed:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-old-time
 * [new ref]         8ba3df7235b76e045ad2a6a00bf2a519280ea9ed -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8ba3df7 Convert to %autorelease and %autochangelog