chore(deps-dev): bump markdownlint-cli2 in the npm-dependencies group

Bumps the npm-dependencies group with 1 update: [markdownlint-cli2](https://github.com/DavidAnson/markdownlint-cli2).


Updates `markdownlint-cli2` from 0.20.0 to 0.21.0
- [Changelog](https://github.com/DavidAnson/markdownlint-cli2/blob/main/CHANGELOG.md)
- [Commits](DavidAnson/markdownlint-cli2@v0.20.0...v0.21.0)

---
updated-dependencies:
- dependency-name: markdownlint-cli2
  dependency-version: 0.21.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: npm-dependencies
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -31,7 +31,7 @@
     "cspell": "9.6.4",
     "markdown-link-check": "3.14.2",
     "markdown-table-formatter": "^1.7.0",
-    "markdownlint-cli2": "^0.20.0"
+    "markdownlint-cli2": "^0.21.0"
   },
   "overrides": {
     "markdown-it": "14.1.1",