[Tests] Add more complex user switching tests

[nan-li]

Description

One Line Summary

Add more complex user switching tests involving multiple calls to login / logout / user updates in a short span.

Details

Motivation

• Adding more testing, and prevent regressions in behavior.
• We have seen bugs come up when changes have been made that changed expected behavior.

Scope

Unit tests

Testing

Unit testing

Added new test class SwitchUserTests

1. testIdentifyUserSuccessfully_thenLogin_sendsCorrectTags - existing test migrated from other file
2. testAnonUser_thenIdentifyUserWithConflict_sendsCorrectUpdatesAndFetchesUser - Starts up with creating the anon user, then a login with conflict happens.
3. testAnonUser_thenIdentifyUserWithConflict_thenLogout_sendsCorrectUpdatesWithNoFetch - Starts up with creating the anon user, then a login with conflict happens, then a logout happens.
4. testAnonUser_thenIdentifyUserWithConflict_thenLogin_sendsCorrectUpdatesAndFetchesUser - Starts up with creating the anon user, then a login with conflict happens, then a login to another user happens.

Manual testing

None, app runs.

Affected code checklist

• [ ] Notifications
  • [ ] Display
  • [ ] Open
  • [ ] Push Processing
  • [ ] Confirm Deliveries
• [ ] Outcomes
• [ ] Sessions
• [ ] In-App Messaging
• [ ] REST API requests
• [ ] Public API changes

Checklist

Overview

• [x] I have filled out all REQUIRED sections above
• [x] PR does one thing
• [x] Any Public API changes are explained in the PR details and conform to existing APIs

Testing

• [x] I have included test coverage for these changes, or explained why they are not needed
• [x] All automated tests pass, or I explained why that is not possible
• [x] I have personally tested this on my device, or explained why that is not possible

Final pass

• [x] Code is as readable as possible.
• [x] I have reviewed this PR myself, ensuring it meets each checklist item

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