chore: add & simplify concurrency setting to CI testing workflow

[bhimrazy]

What does this PR do?

Adds the concurrency setting to the CI testing workflow to match the CI checks workflow, improving resource efficiency by canceling in-progress runs for non-main branches.

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[Copilot]

Pull request overview

This PR adds a concurrency configuration to the CI testing workflow to automatically cancel in-progress workflow runs when new commits are pushed to the same branch (excluding main and release branches), improving CI resource efficiency by matching the pattern already used in the CI checks workflow.

• Adds concurrency group configuration using workflow name, ref, and head_ref
• Configures automatic cancellation of in-progress runs for non-protected branches

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80%. Comparing base (dd96272) to head (cc9974b).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@         Coverage Diff         @@
##           main   #780   +/-   ##
===================================
  Coverage    80%    80%           
===================================
  Files        52     52           
  Lines      7371   7371           
===================================
  Hits       5912   5912           
  Misses     1459   1459           

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