[eas-cli] Add --browser option to eas login

[byronkarlen]

Why

Support for third-party sign in (Apple/Google/GitHub). eas login should eventually default to this but it would be a breaking change.

How

Test Plan

[github-actions]

Subscribed to pull request

File Patterns	Mentions
**/*	@douglowder

Generated by CodeMention

[github-actions]

Size Change: -815 B (0%)

Total Size: 53.3 MB

Filename	Size	Change
./packages/eas-cli/dist/eas-linux-x64.tar.gz	53.3 MB	-815 B (0%)

_{compressed-size-action}

[codecov]

Codecov Report

❌ Patch coverage is 58.82353% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 49.59%. Comparing base (e51fe11) to head (f7e613d).

Files with missing lines	Patch %	Lines
...es/eas-cli/src/user/expoBrowserAuthFlowLauncher.ts	28.58%	5 Missing ⚠️
packages/eas-cli/src/commands/account/login.ts	0.00%	1 Missing ⚠️
...er/fetchSessionSecretAndUserFromBrowserAuthFlow.ts	66.67%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3312      +/-   ##
==========================================
+ Coverage   49.59%   49.59%   +0.01%     
==========================================
  Files         671      671              
  Lines       27991    27992       +1     
  Branches     5793     5798       +5     
==========================================
+ Hits        13879    13880       +1     
  Misses      12921    12921              
  Partials     1191     1191              

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[byronkarlen]

/changelog-entry new-feature Add --browser flag to login command for browser-based authentication

[github-actions]

✅ Thank you for adding the changelog entry!