ci: run tests on all PRs, remove yamllint

[asmacdo]

Summary

• Remove branch filter from pull_request trigger so tests run on PRs targeting any branch
• Remove yamllint from pre-commit (no YAML files to lint besides config files themselves)

Test plan

• Workflow syntax is valid
• Pre-commit passes

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR improves the CI/CD configuration by removing the branch filter from the test workflow so tests run on all pull requests regardless of target branch, and removes yamllint from pre-commit since the repository only has configuration YAML files already validated by the check-yaml hook.

Changes:

• Remove branch filter from pull_request trigger in test workflow to run tests on all PRs
• Remove yamllint hook from pre-commit configuration and delete .yamllint.yaml config file
• Clean up trailing whitespace in tox.ini and CONTRIBUTING.rst

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
.github/workflows/test.yaml	Removes branch filter to allow tests on PRs targeting any branch
.pre-commit-config.yaml	Removes yamllint hook as it's redundant with check-yaml for config files
.yamllint.yaml	Deletes yamllint configuration file no longer needed
CONTRIBUTING.rst	Removes trailing whitespace on line 44
tox.ini	Removes trailing empty line at end of file

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.19%. Comparing base (f35633e) to head (d52f961).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #374      +/-   ##
==========================================
- Coverage   91.38%   91.19%   -0.19%     
==========================================
  Files           8        8              
  Lines        1056     1056              
  Branches      138      138              
==========================================
- Hits          965      963       -2     
- Misses         69       70       +1     
- Partials       22       23       +1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.