chore(package): update eslint to version 6.1.0

Author: greenkeeper[bot]

package.json

@@ -66,7 +66,7 @@
     "babel-preset-env": "^1.7.0",
     "chai": "^4.1.2",
     "codecov": "^3.2.0",
-    "eslint": "^5.15.1",
+    "eslint": "^6.1.0",
     "eslint-config-airbnb-base": "^13.1.0",
     "eslint-plugin-import": "^2.16.0",
     "istanbul": "^v1.1.0-alpha.1",