$ git clone -n https://src.fedoraproject.org/rpms/ghc-NumInstances.git /var/lib/mock/f38-build-side-42-init-devel-730136-27446/root/chroot_tmpdir/scmroot/ghc-NumInstances
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-730136-27446/root/chroot_tmpdir/scmroot/ghc-NumInstances'...
$ git fetch origin e8c70bf9033a4465ba236c816fc0b1dfacd12ddc:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-NumInstances
 * [new ref]         e8c70bf9033a4465ba236c816fc0b1dfacd12ddc -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e8c70bf Convert to %autorelease and %autochangelog