While investigating pytest, I discovered this test class was not
imported in AllTests, so it never ran, and worse, it would always fail
because it would get a NamedUser, and not an AuthenticatedUser. Add it
in it, and hit it with a hammer until it passes.
A few test classes were failing to call tearDown() of the superclass,
which meant the file descriptors of their replydata files were leaking.
Make sure to call it, and switch every other callsite of superclasses by
name to using argument-less super().
Revert an AllTests change that snuck in during release.
1. Added AuthenticatedUser:get_organization_membership
2. Added NamedUser:get_organization_membership
3. Added related tests as GitMembership and related replay data
Steve Kowalik