[Tests] Fix IAM test carryover

[jkasten2]

Description

One Line Summary

Fix test testSetLanguage_afterOnSession hanging due to an issue with InAppMessagingTests not cleaning up it's state.

Details

Motivation

This issue caused tests to stall so the full suite couldn't be run before.

Scope

Only tests affected.

Testing

Manual testing

Ran tests on Xcode 13.3.1.

Affected code checklist

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

Checklist

Overview

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

Testing

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

Final pass

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

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