Move more tests here

[wagenet]

Right now, most tests live in the main graphiti repo. We should move the graphiti-rails ones here.

[richmolj]

I agree conceptually, but particularly for integration specs I'm not sure. Seems like we could get into a situation where an update to graphiti codebase breaks the overall behavior users expect, but we don't know about it because the PR ran specs for graphiti, not graphiti+graphiti-rails

[wagenet]

@richmolj we’d probably want some on both sides ideally.