test: node@13 since it's still in development

Author: jonathanong

.github/workflows/node.js.yml

@@ -11,7 +11,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [10.x, 12.x, 14.x]
+        node-version: [10.x, 12.x, 13.x, 14.x]
 
     env:
       CI: true