ci: upgrade to Node 16

Author: MichaelCurrin

.github/workflows/main.yml

@@ -16,7 +16,7 @@ jobs:
       - name: Use Node.js
         uses: actions/setup-node@v1
         with:
-          node-version: "14.x"
+          node-version: "16.x"
 
       - name: Get cached dependencies
         uses: actions/cache@v2