Run prettier on index.d.ts & Add auth listener callback type

[rakannimer]

Summary

Ran prettier on index.d.ts and added AuthListenerCallback to typescript declaration file and pass it to auth listeners

Checklist

• Supports Android
• Supports iOS
• e2e tests added or updated in /tests/e2e/*
• Updated the documentation in the docs repo
  • LINK TO DOCS PR HERE
• Flow types updated
• Typescript types updated

Release Plan

[TYPES][ENHANCEMENT] [AUTHENTICATION] - Update TS types for auth listeners

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[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #1689 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1689   +/-   ##
=======================================
  Coverage   75.88%   75.88%           
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  Files          72       72           
  Lines        1837     1837           
=======================================
  Hits         1394     1394           
  Misses        443      443