chore(package): update publish-please to version 4.0.0

Closes #58

Author: greenkeeper[bot]

package.json

@@ -30,6 +30,6 @@
     "dirty-chai": "^2.0.1",
     "eslint": "^4.11.0",
     "mocha": "^4.0.1",
-    "publish-please": "^2.2.0"
+    "publish-please": "^4.0.0"
   }
 }