chore(package): update puppeteer to version 2.1.1

Closes #120

Author: greenkeeper[bot]

Diff for: package.json

@@ -71,7 +71,7 @@
     "mocha": "^5.1.1",
     "mocha-typescript": "^1.1.14",
     "nyc": "^13.1.0",
-    "puppeteer": "^1.19.0",
+    "puppeteer": "^2.1.1",
     "sinon": "^6.0.1",
     "source-map-support": "^0.5.6",
     "ts-loader": "^6.1.0",