chore(package): update fetch-mock to version 5.10.0

https://greenkeeper.io/

Author: greenkeeper[bot]

package.json

@@ -24,7 +24,7 @@
     "codecov": "2.1.0",
     "dateformat": "2.0.0",
     "execa": "0.6.3",
-    "fetch-mock": "5.9.4",
+    "fetch-mock": "5.10.0",
     "http-server": "0.9.0",
     "istanbul-instrumenter-loader": "2.0.0",
     "karma": "1.6.0",