Add 'use strict' for node 4.x compat

jacobq · jacobq · commit 0bec41002815 · 2018-03-06T12:23:50.000-06:00
diff --git a/tests/dummy/config/targets.js b/tests/dummy/config/targets.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const browsers = [
   'last 1 Chrome versions',
   'last 1 Firefox versions',
