[MJAVADOC-812] [REGRESSION] maven-javadoc-plugin 3.10.0 creates empty…

[michael-o]

… JARs

This closes #320

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[michael-o]

I am very surprised that no unit or integration test has failed here

Still no test I see...

True, waiting for the confirmation first. If you want to contribute a test that would me more than great.

[krezovic]

I am the same person who reported the bug, but I write from personal account here since I don't have the credentials from the work account on my personal machine.

When I checkout this branch and build the plugin, then build the reproducer I provided, it seems OK

[michael-o]

@pzygielo IT added.