I moved sourcecred/example-git{,hub} to the @sourcecred-test org.
This commit fixes the build given that move.
I've realized that in #1233 I in-advertently made some Git tests that
depend on a snapshot un-updateable. I'm going to compound on that slight
technical debt by skipping the tests that depended on that snapshot. I
recognize and accept that I'll need to pay this down when I resuscitate
the git plugin.
Test plan: `yarn test --full`.
This commit swaps usage over to the new implementation of `cli/load`
(the one that wraps `api/load`) and makes changes throughout the project
to accomodate that we now track instances by Project rather than by
RepoId.
Test plan: Unit tests updated; run `yarn test --full`. Also, for safety:
actually load a project (by whole org, why not) and verify that the
frontend still works.