Change Node version of Build assets Github Action

Fix `??` syntax error during pipeline

Author: Lucas Simeon

.github/workflows/tests.yml

@@ -175,7 +175,7 @@ jobs:
     steps:
       - uses: actions/setup-node@v1
         with:
-          node-version: 12
+          node-version: 16
           registry-url: https://registry.npmjs.org/
 
       - uses: actions/download-artifact@v2