reduce clone and own in the test harness (applies to other repos also)

[rabbah]

the test directory 4 files, only 1 of which is relevant to testing this runtime; the rest are cloned from openwhisk repo and provide the test harness; we need to remove this duplication since it's a maintenance headache in general.

perhaps using the maven dependences is a way of doing that?

[chetanmeh]

So far there was a gradle project dependency on core tests which is being now replaced with Maven dependency via #3. But in both cases we can make use of existing test in core and need not copy it

[csantanapr]

This is nuked now 🎉