$ git clone -n https://src.fedoraproject.org/rpms/ghc-syb.git /var/lib/mock/f38-build-side-42-init-devel-567954-25905/root/chroot_tmpdir/scmroot/ghc-syb
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-567954-25905/root/chroot_tmpdir/scmroot/ghc-syb'...
$ git fetch origin dc14da15e325fce3ad7767e7d0fca22625618ad9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-syb
 * [new ref]         dc14da15e325fce3ad7767e7d0fca22625618ad9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dc14da1 Convert to %autorelease and %autochangelog