fix(package): update @types/event-stream to version 3.3.31

https://greenkeeper.io/

package.json

@@ -32,7 +32,7 @@
     "@types/debug": "0.0.29",
     "@types/elasticsearch": "5.0.13",
     "@types/escape-html": "0.0.19",
-    "@types/event-stream": "3.3.30",
+    "@types/event-stream": "3.3.31",
     "@types/express": "4.0.35",
     "@types/glob": "5.0.30",
     "@types/gm": "1.17.30",