Basic Helm Chart end to end sanity tests

[Kami]

This issue brought up lack of even basic end to end sanity tests - #57.

To begin with, I think having even basic tests which spin up all the services and just run st2 run core.local cmd=date ; st2 run pack install foo or similar (aka what we do on Travis for StackStorm packages) would help a lot and catch such issues early on.

If you think this belongs to the Integration tests issue (#27) feel free to merge those two issues and close this one.

And down the road, having CICD running using Helm Charts will help a lot as well.

[arm4b]

Yeah, I believe it adds +1 to #27