Eslint config tweak

```json
  "eslintConfig": {
    "parserOptions": {
      "ecmaVersion": 6,
      "sourceType": "module"
    },
    "env": {
      "es6": true
    },
    "extends": "eslint:recommended"
  },
```
replace with
```json
  "eslintConfig": {
    "parserOptions": {
      "sourceType": "module"
    },
    "env": {
      "es6": true
    },
    "extends": "eslint:recommended"
  },
```