Patch to MP for generation jobs
During generation jobs, there are no input files and the maxEvents setting is often -1 (that's how we're told to test, normally). This results in a condition that the transform recognizes as having fewer input events than processes, so athenaMP is disabled. Adding an explicit catch for this condition to try to allow MP in these job configurations. Local tests seem to be working.
Thanks to @tsulaia for confirming that I wasn't crazy seeing this.
FYI @ewelina and @lcorpe , and @mavogel for the transform. Happy to have this swept into master if we all thing it's the right thing.