Switch action to Node 16 (#181)

Author: kuhnroyal

action.yml

@@ -23,8 +23,8 @@ inputs:
     description: "The working directory to run the Dart analyzer in (defaults to `./`)."
     default: ./
 runs:
-  using: "node12"
+  using: "node16"
   main: "dist/index.js"
 branding:
-  icon: "hexagon"
+  icon: "search"
   color: "gray-dark"