$ git clone -n https://src.fedoraproject.org/rpms/javacc-maven-plugin.git /var/lib/mock/f40-build-2489786-61655/root/chroot_tmpdir/scmroot/javacc-maven-plugin
Cloning into '/var/lib/mock/f40-build-2489786-61655/root/chroot_tmpdir/scmroot/javacc-maven-plugin'...
$ git fetch origin 786915f8dd3d0ca591ceddaf0250d89b2f1a632a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/javacc-maven-plugin
 * [new ref]         786915f8dd3d0ca591ceddaf0250d89b2f1a632a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 786915f Rebuilt for java-21-openjdk as system jdk