code: public static void repairMultiInstanceAsyncJob(ExecutionEntity execution) {
      ActivityImpl activity = execution.getActivity();
  
      if (!isAsync(activity) && isActivityWrappedInMultiInstanceBody(activity)) {
        execution.setActivity((ActivityImpl) activity.getFlowScope());
      }
    }
docs: When executing an async job for an activity wrapped in an miBody, set the execution to the
  miBody except the wrapped activity is marked as async.
  
  Background: in <= 7.2 async jobs were created for the inner activity, although the
  semantics are that they are executed before the miBody is entered