Implement Projects user management test cases

[seav]

This includes changing roles of org members from one role to another and checking that the user has indeed been granted/revoked permissions. Or we can just check that the updated roles are reflected in project member lists and assume that their indicated role does have the correct permissions as tested by other existing implemented test cases (e.g., only project manager can upload questionnaire, or only data collector can create records, or only project user can view records).