Add tests to ensure workflow doesn't get broken

[erkinalp]

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End-user friendly description of the problem this fixes or functionality that this introduces.
Added comprehensive test suite for workflow token authentication to ensure that token handling in GitHub and GitLab workflows remains functional and secure.

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Give a summary of what the PR does, explaining any non-trivial design decisions.
This PR implements tests for workflow token authentication as requested in issue #7573. It includes:

1. Unit tests for token handling in GitHub workflows

   • Tests for GitHub token validation
   • Tests for GitHub PAT token handling
   • Tests for GitLab token authentication
   • Tests for missing token scenarios

2. Local workflow testing using the act tool

   • Simulated workflow executions with different token types
   • Verification of token validation in workflow files

3. Integration tests for token authentication

   • End-to-end testing of token handling in workflows
   • Tests for token permissions and security constraints

The tests use mocking to avoid requiring actual API calls while still providing comprehensive coverage of token handling functionality.

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Link of any specific issues this addresses.
Fixes #7573

Link to Devin run: https://app.devin.ai/sessions/9e4698444aa147bf8d970a4faec2de3e

Co-authored-by: Erkin Alp Güney [email protected]