$ git clone -n https://src.fedoraproject.org/rpms/zathura-pdf-mupdf.git /var/lib/mock/f40-build-804218-144467/root/chroot_tmpdir/scmroot/zathura-pdf-mupdf
Cloning into '/var/lib/mock/f40-build-804218-144467/root/chroot_tmpdir/scmroot/zathura-pdf-mupdf'...
$ git fetch origin 7dbe2704d1c37d361af4fb72e4525bc854ea2900:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/zathura-pdf-mupdf
 * [new ref]         7dbe2704d1c37d361af4fb72e4525bc854ea2900 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7dbe270 Build against mupdf shared library