[cli] CI check and environment flag override for update

[douglowder]

Why

Provide a way to override the new requirement for the --environment flag in eas update.

How

Modify the check to skip when the EAS_UPDATE_SKIP_ENVIRONMENT_CHECK variable is set to a boolish value (1 or true).

Add the CI flag to the tests for whether we should skip the check in a CI environment.

Test Plan

New unit tests added.

[douglowder]

• [cli] CI check and environment flag override for update #3442 👈 (View in Graphite)
• main

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[github-actions]

Subscribed to pull request

File Patterns	Mentions
packages/eas-cli/src/update/**	@wschurman, @quinlanj
packages/eas-cli/src/commands/update/**	@wschurman, @quinlanj

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[github-actions]

✅ Thank you for adding the changelog entry!

[codecov]

Codecov Report

❌ Patch coverage is 88.88889% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 52.79%. Comparing base (1d36f4f) to head (c914a38).

Files with missing lines	Patch %	Lines
packages/eas-cli/src/update/utils.ts	88.89%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3442      +/-   ##
==========================================
+ Coverage   52.78%   52.79%   +0.01%     
==========================================
  Files         809      809              
  Lines       34047    34053       +6     
  Branches     7075     7076       +1     
==========================================
+ Hits        17969    17975       +6     
  Misses      15997    15997              
  Partials       81       81              

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