$ git clone -n https://src.fedoraproject.org/rpms/ghc-echo.git /var/lib/mock/f42-build-877385-180226/root/chroot_tmpdir/scmroot/ghc-echo
Cloning into '/var/lib/mock/f42-build-877385-180226/root/chroot_tmpdir/scmroot/ghc-echo'...
$ git fetch origin 5ef139089583d9adbfed545eb54eccd1569d869c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-echo
 * [new ref]         5ef139089583d9adbfed545eb54eccd1569d869c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5ef1390 Rebuilt for https://fedoraproject.org/wiki/Fedora_42_Mass_Rebuild