Update ESLint to next major version
Follow up to: !2335 (closed), to update to the latest major version of ESLint.
A newer parser was required, because the old one is deprecated: https://www.npmjs.com/package/babel-eslint.
Follow up to: !2335 (closed), to update to the latest major version of ESLint.
A newer parser was required, because the old one is deprecated: https://www.npmjs.com/package/babel-eslint.