chore(package): update cross-env to version 7.0.1

Closes #61

Author: greenkeeper[bot]

package.json

@@ -46,7 +46,7 @@
     "babel-jest": "^24.9.0",
     "babel-loader": "^8.0.5",
     "coveralls": "^3.0.2",
-    "cross-env": "^6.0.0",
+    "cross-env": "^7.0.1",
     "css": "^2.2.4",
     "detect-port-alt": "^1.1.6",
     "eslint": "^6.1.0",