fix(package): update pm2 to version 4.4.0

Closes #131

Author: greenkeeper[bot]

package.json

@@ -47,7 +47,7 @@
     "mysql": "^2.15.0",
     "npm": "^6.0.0",
     "path": "^0.12.7",
-    "pm2": "^3.0.0",
+    "pm2": "^4.4.0",
     "puppeteer": "^1.0.0",
     "raven": "^2.4.2",
     "request-promise-native": "^1.0.5",