chore(package): update mocha to version 7.0.1

Closes #2

Author: greenkeeper[bot]

package.json

@@ -21,7 +21,7 @@
     "webrtc-signal-http": "^1.1.1"
   },
   "devDependencies": {
-    "mocha": "^5.0.0",
+    "mocha": "^7.0.1",
     "supertest": "^3.0.0"
   }
 }