Update action.yml

Node.js 16 actions are deprecated. Please update the following actions to use Node.js 20: replicatedhq/required-workflows/.github/actions/pr-labels@main. For more information see: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/.

.github/actions/pr-labels/action.yml

@@ -2,10 +2,10 @@ name: "Check PR labels"
 description: "Check required PR labels are present"
 author: "Replicated"
 runs:
-  using: 'node16'
+  using: 'node20'
   main: 'dist/index.js'
 inputs:
   token:
     description: The GitHub token to use when calling the API
     default: ${{ github.token }}
-    required: false
+    required: false