$ git clone -n https://src.fedoraproject.org/rpms/fedora-obsolete-packages.git /var/lib/mock/f38-build-side-42-init-devel-904050-28617/root/chroot_tmpdir/scmroot/fedora-obsolete-packages
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-904050-28617/root/chroot_tmpdir/scmroot/fedora-obsolete-packages'...
$ git fetch origin ff5fe6727229ec8890e01eb6aa8750ed33eee617:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/fedora-obsolete-packages
 * [new ref]         ff5fe6727229ec8890e01eb6aa8750ed33eee617 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ff5fe67 Obsolete recordmydesktop