$ git clone -n https://src.fedoraproject.org/rpms/ghc-echo.git /var/lib/mock/f38-build-side-42-init-devel-842072-28415/root/chroot_tmpdir/scmroot/ghc-echo
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-842072-28415/root/chroot_tmpdir/scmroot/ghc-echo'...
$ git fetch origin 687d87ff249b23d144c79e1bc3ea2e4a6bb70602:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-echo
 * [new ref]         687d87ff249b23d144c79e1bc3ea2e4a6bb70602 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 687d87f Convert to %autorelease and %autochangelog