Update mocha to the latest version 🚀 (#26)

* chore(package): update mocha to version 5.0.0

* chore(package): update lockfile

https://npm.im/greenkeeper-lockfile

package.json

@@ -58,7 +58,7 @@
     "chai": "^4.1.2",
     "codecov": "^3.0.0",
     "cross-env": "^5.1.0",
-    "mocha": "^4.0.1",
+    "mocha": "^5.0.0",
     "nyc": "^11.2.1",
     "snazzy": "^7.0.0",
     "standard": "^10.0.3"

yarn.lock

@@ -1557,7 +1557,7 @@ form-data@~2.1.1:
     combined-stream "^1.0.5"
     mime-types "^2.1.12"
 
-fs-extra@5.0.0:
+fs-extra@^5.0.0:
   version "5.0.0"
   resolved "https://registry.yarnpkg.com/fs-extra/-/fs-extra-5.0.0.tgz#414d0110cdd06705734d055652c5411260c31abd"
   dependencies:
@@ -2283,9 +2283,9 @@ mkdirp@0.5.1, "mkdirp@>=0.5 0", mkdirp@^0.5.0, mkdirp@^0.5.1:
   dependencies:
     minimist "0.0.8"
 
-mocha@^4.0.1:
-  version "4.0.1"
-  resolved "https://registry.yarnpkg.com/mocha/-/mocha-4.0.1.tgz#0aee5a95cf69a4618820f5e51fa31717117daf1b"
+mocha@5.0.0:
+  version "5.0.0"
+  resolved "https://registry.yarnpkg.com/mocha/-/mocha-5.0.0.tgz#cccac988b0bc5477119cba0e43de7af6d6ad8f4e"
   dependencies:
     browser-stdout "1.3.0"
     commander "2.11.0"