always returns an empty array. The logic at:
appears to be incorrect (at least, it is in my testing - I'm using maven 3.3.9).
I couldn't find any documentation for what an execution project is supposed to be. Based on what I can glean from https://issues.apache.org/jira/browse/MNG-3941, it sounds like it's not appropriate in this use case.
Therefore, I'm attaching a PR that remove the use of executionProject and makes work as intended: