$ git clone -n https://src.fedoraproject.org/rpms/rubygem-hrx.git /var/lib/mock/f39-build-1458414-33057/root/chroot_tmpdir/scmroot/rubygem-hrx
Cloning into '/var/lib/mock/f39-build-1458414-33057/root/chroot_tmpdir/scmroot/rubygem-hrx'...
$ git fetch origin 3b5348fd71487bace140a413e84d783132f5aea1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-hrx
 * [new ref]         3b5348fd71487bace140a413e84d783132f5aea1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3b5348f Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild