Update eslint-config-create-full-stack packages when create-react-app v4.0 is released

[tiagob]

Fixes sindresorhus/eslint-plugin-unicorn#755
Which was fixed in sindresorhus/eslint-plugin-unicorn#756
But requires facebook/create-react-app#8978
Which isn't released yet. It's tracked https://github.com/facebook/create-react-app/milestone/69

[tiagob]

Dependent on react-scripts v4