bump actions checkout

Author: coado

.github/actions/diff-js-api-breaking-changes/action.yml

@@ -4,7 +4,7 @@ runs:
   using: composite
   steps:
     - name: Checkout PR branch
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ github.event.pull_request.head.sha }}