[Bug] Fix warning about decoding a boolean

[nan-li]

Description

One Line Summary

Fixes a warning about decoding an object as a boolean by using the decode boolean method.

Details

Use decodeBool instead of decodeObject as Bool, for the flag indicating if a live activities request is successful.

This was added in #1377, and we didn't catch the warnings.

Motivation

Xcode warning about future errors.

*** -[NSKeyedUnarchiver decodeObjectForKey:]: value for key (requestSuccessful) is not an object. 
This will become an error in the future.

*** -[NSKeyedUnarchiver decodeObjectForKey:]: value for key (requestSuccessful) is not an object. 
This will become an error in the future.

Scope

Decoding a boolean from cache, which defaults to false if not there, which is unlikely to happen as there are guards ensuring other properties are successfully decoded.

Testing

Manual testing

Encountered this purple warning message in the Xcode log, then went away.

Affected code checklist

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

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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