[MPH-189] Get rid of commons lang3 dependency

[Giovds]

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[Giovds]

This requires the DefaultArtifactVersion to drop commons-lang3 in the maven-artifact module. This was just recently done with https://issues.apache.org/jira/browse/MNG-8146 and PR #1564 in core.

After that version bump is required here

Edit: it could be acceptable to just keep the dependency from exclusions as it is only used in test scope and will be removed automatically once maven-artifact dependency is version bumped. So I removed the exclusions and enforcer rule.

[slawekjaranowski]

Change looks ok ...

But we should figure out how to avoid calling private methods at all - of course it is another issue and PR

[Giovds]

I agree.

The main reason I kept it, is because it's used only for test code which was already based on reflection. I didn't want to changing the access modifiers of the actual class. Like you said, I wanted to focus this PR on removing the dependency.

[michael-o]

Will try to check in a couple of days.

[michael-o]

You so often repeat the same lines that it would make sense to move that to a private method.

[michael-o]

Good to squash and merge.