[MNG-7672] Fork should only execute the project and its submodules

[gnodet]

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[pzygielo]

Just about vocabulary.
Commit comment and JIRA issue mention children.
Code is about aggregator and submodules.
As I understand it - being submodule does not mean anything about being child, and is not related with inheritance. Perhaps this could be re-worded to not mix the two.

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https://maven.apache.org/pom.html#a-final-note-on-inheritance-v-aggregation

[cstamas]

Interesting fact; this PR fixes code added to Maven 3.0-RC1 (!!!) but the Javadoc for aggregator says literally this what this PR introduces (so the two was not aligned since 3.0-RC1): https://maven.apache.org/ref/3.8.7/maven-plugin-api/apidocs/org/apache/maven/plugin/descriptor/MojoDescriptor.html#isAggregator--

[gnodet]

Interesting fact; this PR fixes code added to Maven 3.0-RC1 (!!!) but the Javadoc for aggregator says literally this what this PR introduces (so the two was not aligned since 3.0-RC1): https://maven.apache.org/ref/3.8.7/maven-plugin-api/apidocs/org/apache/maven/plugin/descriptor/MojoDescriptor.html#isAggregator--

Yes, I saw the javadoc for the isAggregator and it guided me in finding this fix !

[cstamas]

So, what is the status of this (am more interested in 3.9 backport), is this fix confirmed? When is merge expected?

[gnodet]

So, what is the status of this (am more interested in 3.9 backport), is this fix confirmed? When is merge expected?

#969 and #970
I think @michael-o wanted to review this PR, right ?