$ git clone -n https://src.fedoraproject.org/rpms/rubygem-ruby-shadow.git /var/lib/mock/f42-build-865211-172845/root/chroot_tmpdir/scmroot/rubygem-ruby-shadow
Cloning into '/var/lib/mock/f42-build-865211-172845/root/chroot_tmpdir/scmroot/rubygem-ruby-shadow'...
$ git fetch origin fa13bebe8fe091204d7202a2d80b91700e7c7419:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-ruby-shadow
 * [new ref]         fa13bebe8fe091204d7202a2d80b91700e7c7419 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fa13beb Rebuild for https://fedoraproject.org/wiki/Changes/Ruby_3.4