fix(eas-cli): Check if expo is resolvable before assuming it's installed

[kitten]

Summary

We'll have to share a check on whether expo is resolvable with isExpoInstalled, to make it stricter, since the check is used to see if expo is installed, not just to see if it's in dependencies. We often use this as a prerequisite to see if we can call the Expo CLI. The check needs to align with spawnExpoCommand to ensure we don't pass into spawnExpoCommand when we can't

Test Plan

[github-actions]

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File Patterns	Mentions
**/*	@douglowder

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[codecov]

Codecov Report

❌ Patch coverage is 14.28571% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 56.99%. Comparing base (29909b2) to head (dbaa3f8).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
packages/eas-cli/src/project/projectUtils.ts	10.00%	9 Missing ⚠️
packages/eas-cli/src/utils/expoCli.ts	25.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3748      +/-   ##
==========================================
+ Coverage   56.64%   56.99%   +0.36%     
==========================================
  Files         906      902       -4     
  Lines       39041    38869     -172     
  Branches     8154     8124      -30     
==========================================
+ Hits        22110    22149      +39     
+ Misses      15454    15263     -191     
+ Partials     1477     1457      -20     

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[github-actions]

✅ Thank you for adding the changelog entry!