$ git clone -n https://src.fedoraproject.org/rpms/rust-synstructure.git /var/lib/mock/f39-build-1517278-35708/root/chroot_tmpdir/scmroot/rust-synstructure
Cloning into '/var/lib/mock/f39-build-1517278-35708/root/chroot_tmpdir/scmroot/rust-synstructure'...
$ git fetch origin 7bbb3de4d0fb23be6d82390d738b11b3e2fc758d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-synstructure
 * [new ref]         7bbb3de4d0fb23be6d82390d738b11b3e2fc758d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7bbb3de Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild