Adds workflow:validate command

[jonsamp]

Why

This adds a command to validate YAML in workflow configuration files.

Screenshots

Valid YAML output

Invalid YAML output

Test Plan

Create a .yml file and test it with eas workflow:validate path/to/file.yml. You should see output like the screenshots above.

• Make sure non existent files result in an error
• Make sure non .yml/.yaml files result in an error
• Make sure bad YAML results in an error
• Make sure good YAML results in no error

[linear]

ENG-13772 Create workflows EAS CLI command

[github-actions]

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[github-actions]

Size Change: -488 kB (-0.92%)

Total Size: 52.5 MB

Filename	Size	Change
./packages/eas-cli/dist/eas-linux-x64.tar.gz	52.5 MB	-488 kB (-0.92%)

_{compressed-size-action}

[codecov]

Codecov Report

Attention: Patch coverage is 23.07692% with 30 lines in your changes missing coverage. Please review.

Project coverage is 52.96%. Comparing base (a212662) to head (5633e1e).

Files with missing lines	Patch %	Lines
packages/eas-cli/src/commands/workflow/validate.ts	23.08%	30 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2650      +/-   ##
==========================================
- Coverage   53.01%   52.96%   -0.05%     
==========================================
  Files         567      568       +1     
  Lines       21647    21686      +39     
  Branches     4242     4247       +5     
==========================================
+ Hits        11474    11483       +9     
- Misses      10143    10173      +30     
  Partials       30       30              

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