feat(eas-cli): add observe metrics command

[Ubax]

Why

Please describe the motivation for this PR, and link to relevant GitHub issues, forums posts, or feature requests.

How

How did you build this feature or fix this bug and why?

Test Plan

Please describe how you tested this change and how a reviewer could reproduce your test, especially if this PR does not include automated tests! If possible, please also provide terminal output and/or screenshots demonstrating your test/reproduction.

[codecov]

Codecov Report

❌ Patch coverage is 96.72131% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 52.72%. Comparing base (0c32aa3) to head (abf3904).

Files with missing lines	Patch %	Lines
...ckages/eas-cli/src/graphql/queries/ObserveQuery.ts	27.28%	8 Missing ⚠️
packages/eas-cli/src/commands/observe/metrics.ts	98.42%	1 Missing ⚠️
packages/eas-cli/src/observe/formatMetrics.ts	98.79%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3401      +/-   ##
==========================================
+ Coverage   52.32%   52.72%   +0.40%     
==========================================
  Files         807      815       +8     
  Lines       33868    34173     +305     
  Branches     7033     7115      +82     
==========================================
+ Hits        17719    18015     +296     
- Misses      14750    14759       +9     
  Partials     1399     1399              

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[github-actions]

✅ Thank you for adding the changelog entry!