chore(package): update eslint to version 6.4.0

Closes #43

Author: greenkeeper[bot]

package.json

@@ -35,7 +35,7 @@
     "babel-preset-airbnb": "^2.6.0",
     "body-parser": "^1.18.3",
     "chai": "^4.2.0",
-    "eslint": "^5.9.0",
+    "eslint": "^6.4.0",
     "eslint-config-airbnb": "^17.1.0",
     "eslint-plugin-import": "^2.14.0",
     "eslint-plugin-jsx-a11y": "^6.1.2",