Remove duplication in Report.js

[marcaaron]

Details

Pusher subscription logic in Report.js is pretty wild and lots of copy pasta is used. Cleaning this up a bit.

Fixed Issues

$ https://github.com/Expensify/Expensify/issues/201111

Tests

1. Not much apart from regressions around various realtime features like report comments
2. Verify that you are subscribed to the Pusher channels here

• Verify that no errors appear in the JS console

QA Steps

1. None apart from regressions around various realtime features like report comments

• Verify that no errors appear in the JS console

[OSBotify]

✋ This PR was not deployed to staging yet because QA is ongoing. It will be automatically deployed to staging after the next production release.

[OSBotify]

🚀 Deployed to staging by @timszot in version: 1.1.43-0 🚀

platform	result
🤖 android 🤖	success ✅
🖥 desktop 🖥	success ✅
🍎 iOS 🍎	success ✅
🕸 web 🕸	success ✅

[OSBotify]

🚀 Deployed to production by @roryabraham in version: 1.1.43-2 🚀

platform	result
🤖 android 🤖	success ✅
🖥 desktop 🖥	success ✅
🍎 iOS 🍎	success ✅
🕸 web 🕸	success ✅