Avoid duplicating test code between e2e & canary

[spypsy]

We have a few tests that run the same path in both e2e & canary flows. We previously used test suites exported from the tested package itself but this is not a great solution, as it pollutes the actual code that's necessary to run the packages.
We should figure out a way to share the test code without exporting it from the packages

[benesjan]

One way to tackle this would be to have a separate package which would contain the test suites. That way we would not clutter the original package.

OTOH this is not ideal for tests like Aztec RPC Server because this breaks a norm a bit because the unit test would not longer be in the same package.

[spypsy]

This is pretty much what I have in mind.
I think we should have dir just for tests that will replace end-to-end and then having this tests run on different levels of mocking. Most e2e tests currently could either be run against Sandbox or a plain RPC Server.
I see unit tests as a separate thing and they should be in the project's directory. They should be run just by yarn test and not require any extra setup