feat: use latest android & ios Firebase SDKs version

[russellwheatley]

addresses Mike's issue: #3943

Description

• Updated Gradle version to latest 6.5.1 for each package.
• Updated Android Gradle plugin to 4.0.0 for each package.
• Updated buildTools to version 29.0.2 for tests android/build.gradle, minimum required for latest Android Gradle plugin.
• Ran pod update within tests/ios to upgrade pods based on what is allowed according to Podfile and also to upgrade the GoogleUtilities pods to patched working version 6.7.1 (6.7 was a recently released broken version used by Firebase iOS SDK)
• Updated Android Crashlytics SDK for tests.
• Updated iOS SDK to 6.28.1

Related issues

Release Summary

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

Test Plan

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[mikehardy]

Hell good sir - as mentioned on the issue, happy to collaborate to flush out whatever is causing android compile errors for me. The IID one is obvious (it's just not versioned in the BoM, so....) but that GoogleApiAvailability thing is really odd - don't want anyone else to compile-fail on Android first thing, terrible DX

[mikehardy]

Well dang. Worked just fine it seems. With the demo script at least it's all built from scratch each time so the answer is in there somewhere, what the heck is going on...