feat: add custom events support

[fadi-george]

Description

One Line Summary

• adds custom events support for the react native package

Details

• sets versions of android and ios to versions that have custom events logic
• expose android trackEvent method via RNOneSignal.java
• expose ios trackEvent method via RCTOneSignalEventEmitter.m
• add new trackEvent react-native method via src/index.ts
• removed material ui package for react native example
• adds trackEvent demo action for the example project

Motivation

Code change is to allow developers to use custom-events with the react-native package.

Testing

Manual testing

Run ios and android emulators and tested the trackEvent action. See screenshot of the custom event actually being recorded.

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
  • If it is hard to explain how any codes changes are related to each other then it most likely needs to be more than one PR
• 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.
  • Simplify with less code, followed by splitting up code into well named functions and variables, followed by adding comments to the code.
• I have reviewed this PR myself, ensuring it meets each checklist item
  • WIP (Work In Progress) is ok, but explain what is still in progress and what you would like feedback on. Start the PR title with "WIP" to indicate this.

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This change is 

[nan-li]

Do not merge to main

[nan-li]

Approved but blocking until the base of the PR changes