Group Dependabot updates

[samdark]

Replicates the Dependabot grouping configuration from yiisoft/package-template so GitHub Actions updates are grouped into a single PR and Composer dependency updates are grouped into a single PR.

[Copilot]

Pull request overview

Note

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Adds Dependabot grouping configuration so GitHub Actions updates and Composer dependency updates are each bundled into a single PR, matching the referenced yiisoft/package-template setup.

Changes:

• Group all GitHub Actions (github-actions) dependency updates into one PR.
• Group all Composer (composer-dependencies) dependency updates into one PR.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (148409d) to head (c075bcd).

Additional details and impacted files

@@           Coverage Diff            @@
##             master    #118   +/-   ##
========================================
  Coverage      0.00%   0.00%           
  Complexity      110     110           
========================================
  Files            15      15           
  Lines           287     287           
========================================
  Misses          287     287           

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