MEDIUM: lua: only allow actions to yield if not in a final call

MEDIUM: lua: only allow actions to yield if not in a final call

Actions may yield but must not do it during the final call from a ruleset
because it indicates there will be no more opportunity to complete or
clean up. This is indicated by ACT_FLAG_FINAL in the action's flags,
which must be passed to hlua_resume().

Thanks to this, an action called from a TCP ruleset is properly woken
up and possibly finished when the client disconnects.