chore(package): update yeoman-test to version 2.3.0

Closes #12

Author: greenkeeper[bot]

package.json

@@ -31,6 +31,6 @@
     "jshint": "^2.9.4",
     "mocha": "^4.0.0",
     "yeoman-assert": "^3.0.0",
-    "yeoman-test": "^1.6.0"
+    "yeoman-test": "^2.3.0"
   }
 }