$ git clone -n https://src.fedoraproject.org/rpms/rust-cobs.git /var/lib/mock/f45-build-40861-776/root/chroot_tmpdir/scmroot/rust-cobs
Cloning into '/var/lib/mock/f45-build-40861-776/root/chroot_tmpdir/scmroot/rust-cobs'...
$ git fetch origin 141bac5ce3fda52ccf9239dfad0a74f8a8097596:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-cobs
 * [new ref]         141bac5ce3fda52ccf9239dfad0a74f8a8097596 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 141bac5 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild