$ git clone -n https://src.fedoraproject.org/rpms/rubygem-mechanize.git /var/lib/mock/f45-build-35038-693/root/chroot_tmpdir/scmroot/rubygem-mechanize
Cloning into '/var/lib/mock/f45-build-35038-693/root/chroot_tmpdir/scmroot/rubygem-mechanize'...
$ git fetch origin edd6031efa2acaa261229ecfae19551371d2f1cb:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-mechanize
 * [new ref]         edd6031efa2acaa261229ecfae19551371d2f1cb -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at edd6031 2.14.1