Update DavidAnson/markdownlint-cli2-action action to v18

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
DavidAnson/markdownlint-cli2-action	action	major	v17.0.0 -> v18.0.0

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Release Notes

DavidAnson/markdownlint-cli2-action (DavidAnson/markdownlint-cli2-action)

### [`v18.0.0`](https://redirect.github.com/DavidAnson/markdownlint-cli2-action/releases/tag/v18.0.0): Update markdownlint version (markdownlint-cli2 v0.15.0, markdownlint v0.36.1). [Compare Source](https://redirect.github.com/DavidAnson/markdownlint-cli2-action/compare/v17.0.0...v18.0.0)

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Configuration

📅 Schedule: Branch creation - "before 4am" in timezone America/Los_Angeles, Automerge - At any time (no schedule defined).

🚦 Automerge: Enabled.

♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box

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This PR was generated by Mend Renovate. View the repository job log.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 89.86%. Comparing base (a1a1c1f) to head (508cb1f). Report is 1 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2776 +/- ## ======================================= Coverage 89.86% 89.86% ======================================= Files 107 107 Lines 10997 10997 Branches 50 50 ======================================= Hits 9883 9883 Misses 1054 1054 Partials 60 60 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

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🚨 Try these New Features:

• Flaky Tests Detection - Detect and resolve failed and flaky tests
• JS Bundle Analysis - Avoid shipping oversized bundles