chore(package): update gulp-mocha to version 7.0.2

Closes #13

Author: greenkeeper[bot]

package.json

@@ -64,7 +64,7 @@
     "gulp-istanbul": "^1.1.1",
     "gulp-jshint": "^2.0.2",
     "gulp-load-plugins": "^1.4.0",
-    "gulp-mocha": "^4.3.1",
+    "gulp-mocha": "^7.0.2",
     "jade": "^1.9.0",
     "jshint": "^2.9.4",
     "jshint-stylish": "^2.0.0",