Update stale.yml to use stale v5 and node 16

.github/workflows/stale.yml

@@ -18,7 +18,7 @@ jobs:
       pull-requests: write
 
     steps:
-    - uses: actions/stale@v4
+    - uses: actions/stale@v5
       with:
           days-before-stale: 40
           days-before-close: 5