Clean up old requireUpperBoundDeps exclusions

[jglick]

Noticed looking at #456. If I read #269 right, these have been unnecessary since 4.0.

[basil]

Have you tried this with some real-world plugins? With this PR I get build errors in most plugins I maintain, typically for JNA and Guava, in all but the very latest cores. Personally I am -0; I think this PR is a bit too aggressive but won't stand in the way. I would be in favor of this PR if the JNA and Guava exclusions were retained. I think we need to wait until more plugins adopt recent cores before it will be practical to start enforcing correctness of JNA and Guava dependencies.

[jglick]

Have you tried this with some real-world plugins?

Nope, just the ITs.

in all but the very latest cores

So the existing comments are wrong?

[basil]

So the existing comments are wrong?

I cannot understand the existing comments, so I cannot judge them.

[jglick]

#477 is actually doing the opposite.