$ git clone -n https://src.fedoraproject.org/rpms/javassist.git /var/lib/mock/f40-build-2729726-73194/root/chroot_tmpdir/scmroot/javassist
Cloning into '/var/lib/mock/f40-build-2729726-73194/root/chroot_tmpdir/scmroot/javassist'...
$ git fetch origin 857f13c404d7749c758adf5d3318bc818c7f786d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/javassist
 * [new ref]         857f13c404d7749c758adf5d3318bc818c7f786d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 857f13c Rebuilt for java-21-openjdk as system jdk