ESLINT: Parsing error: Unexpected token in package.json
ESLint is for validating JavaScript, not JSON.
From the website:
ESLint
The pluggable linting utility for JavaScript and JSX
[emphasis mine]
(You can try your code on the online demo here, and you get the same error)
If you want to use ESLint on a JSON file, you could use a package like eslint-plugin-json.