$ git clone -n https://src.fedoraproject.org/rpms/rust.git /var/lib/mock/f41-build-861816-170412/root/chroot_tmpdir/scmroot/rust
Cloning into '/var/lib/mock/f41-build-861816-170412/root/chroot_tmpdir/scmroot/rust'...
$ git fetch origin 64ec772902aea5ef1212ce43e76c213b2d8211d9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust
 * [new ref]         64ec772902aea5ef1212ce43e76c213b2d8211d9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 64ec772 Update to Rust 1.83.0