chore(deps): update actions/checkout action to v6 (#69)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/docs.yml

@@ -22,7 +22,7 @@ jobs:
     runs-on: macos-15
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup Xcode
         uses: maxim-lobanov/setup-xcode@v1