Builds have been failing lately because of a recent Jenkins bug with
Maven 3.5.x versions, even when Maven finished successfully. I moved our
jobs back to build with Maven 3.3.9 as a workaround. Another workaround
would have been to disable the "Publish FindBugs analysis results"
checkbox, which seems to trigger the problem. This might make sense for us
anyway, since we already fail the build on new non-trivial findbugs issues.
Here's an example of a recent failure.
Including INFRA on this thread, in case it affects decisions to remove old
versions of Maven or otherwise affects Jenkins maintenance in any way.