API documentation for JSON comparison

## Before Logging a feature request
- [ ] I have searched in this repository's issues to see if it has already been reported.
- [ ] This is not a Security Disclosure, otherwise please follow the guidelines in [Security Policy](https://github.com/adobe/aepsdk-testutils-ios/security/policy).

## Feature Request Summary

Linked to task on Android: https://github.com/adobe/aepsdk-testutils-android/issues/39

Create documentation for the JSON comparison APIs.

We will reuse the documentation we create in Android and modify it for iOS.

## Current Behavior

## Desired Behavior

## Sample Code that illustrates the request
```swift
//sample code

```

No iOS file, test, or documentation entry point is identified. Start by reviewing the linked Android task and the existing JSON comparison APIs in this repository, then adapt the Android documentation for iOS. Done means the iOS APIs have clear documentation covering their JSON comparison usage.

Written by the indexing model from the issue text.