chore(deps): update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/docs.yml

@@ -6,7 +6,7 @@ jobs:
     name: Documentation Lint
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: actions/setup-node@v4
         with:
           node-version: '20'