Updates parent pom, various plugins or deps, tidies up inconsistent versions
and consolidates to inherited version where possible, define properties for
some versions where not. Disables some problematic tests on JDK16+ for now.
Drops DS test dep back 1 version to remove a specific breakage affecting
multiple tests/modules, introduced after its upgrade in commit
9e70b26368.
- Build examples using release profile on JDK8, like the Travis job.
- Build the examples on JDK11+ (unlike the Travis job).
- Add a workflow_dispatch trigger to allow manual start of new runs
without using the rerun button and overrwriting previous logs.