fix(auth, ios): factorId nil check

[vargajacint]

Description

Sometimes the hint.factorID (in the firebaseUserToDict function) is retuning nil value and this could cause app crash. I've tried to described my journey with this issue in this comment

Related issues

Fixes #7080

Release Summary

Auth module - nil check in the getJSFactorId function

Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
  • Yes
• My change supports the following platforms;
  • Android
  • iOS
• My change includes tests;
  • e2e tests added or updated in packages/\*\*/e2e
  • jest tests added or updated in packages/\*\*/__tests__
• I have updated TypeScript types that are affected by my change.
• This is a breaking change;
  • Yes
  • No

🔥

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
react-native-firebase	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jan 6, 2024 7:31pm
react-native-firebase-next	🛑 Canceled (Inspect)			Jan 6, 2024 7:31pm

[CLAassistant]

All committers have signed the CLA.

[mikehardy]

Hey - thanks a bunch for working through this. I'm sorry it is crashing for you and I'm certain we need a change here so I really appreciate the investigation

I've let some comments on the specific direction for the change and I'm curious for your thoughts on the comments - after a little conversation between us I'm sure we'll come up with something that we agree on and we can get a fix released for this

[vargajacint]

Hey @mikehardy,
Yeah you were right, I've applied your suggested changes! Thank you, and happy new year!

[mikehardy]

This looks clean and easy to me - I'm a +1 on it - does it work for you to solve the crash in testing?

[mikehardy]

Already passed iOS, android code didn't change --> good to go