$ git clone -n https://src.fedoraproject.org/rpms/rust-rustc-test.git /var/lib/mock/f39-build-1636576-39925/root/chroot_tmpdir/scmroot/rust-rustc-test
Cloning into '/var/lib/mock/f39-build-1636576-39925/root/chroot_tmpdir/scmroot/rust-rustc-test'...
$ git fetch origin fc88c54a847b6afb3b879e3c2f741c3410e33627:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rustc-test
 * [new ref]         fc88c54a847b6afb3b879e3c2f741c3410e33627 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fc88c54 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild