$ git clone -n https://src.fedoraproject.org/rpms/mpfr.git /var/lib/mock/f40-build-786664-134489/root/chroot_tmpdir/scmroot/mpfr
Cloning into '/var/lib/mock/f40-build-786664-134489/root/chroot_tmpdir/scmroot/mpfr'...
$ git fetch origin 5922b52bac87b4daa294fa5898ec79ee67b17d28:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mpfr
 * [new ref]         5922b52bac87b4daa294fa5898ec79ee67b17d28 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5922b52 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild