Fixed VSCode warning for tslint trailing-comma

Incorrect type. Expected "array"

Author: comerc

packages/react-scripts/template/tslint.json

@@ -66,7 +66,7 @@
         "semicolon": [true, "always"],
         "switch-default": true,
 
-        "trailing-comma": false,
+        "trailing-comma": [false],
 
         "triple-equals": [ true, "allow-null-check" ],
         "typedef": [