Bump actions/setup-node from 6 to 7

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 6 to 7.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](actions/setup-node@v6...v7)

---
updated-dependencies:
- dependency-name: actions/setup-node
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/markdownlint.yml

@@ -15,7 +15,7 @@ jobs:
     steps:
     - uses: actions/checkout@v7
     - name: Use Node.js
-      uses: actions/setup-node@v6
+      uses: actions/setup-node@v7
       with:
         node-version: latest
     - name: Run Markdownlint