docs: remove nuxt.js quickstart in readme

<!-- Thank you for contributing! --> ### Description <!-- Please insert your description here and provide especially info about the "what" this PR is solving --> It seemed to make it difficult to use with Nuxt 3, so remove that section. #103 ### What is the purpose of this pull request? <!-- (put an "X" next to an item) --> - [ ] Bug fix - [ ] New Feature - [x] Documentation update - [ ] Other