chore(package): update eslint to version 6.4.0

Closes #60

Author: greenkeeper[bot]

package.json

@@ -41,7 +41,7 @@
     "babelify": "^8.0.0",
     "commitizen": "^3.0.5",
     "cz-conventional-changelog": "^2.1.0",
-    "eslint": "^5.0.0",
+    "eslint": "^6.4.0",
     "eslint-config-finn": "^3.0.1",
     "eslint-config-finn-prettier": "^3.0.2",
     "husky": "^1.3.0",