Fix Nuxt 3 tests

[leoortizz]

Rename Nuxt 3 from nuxt3 to nuxt, and Nuxt 2 from nuxt to nuxt2.

The Nuxt 3 test was having errors in the postinstall script that runs nuxt prepare due to the nuxt dependency in the parent directory. Found that this could be the issue from this comment: nuxt/nuxt#19866 (comment)

[alexastrum]

@leoortizz, pls run npm i and push latest package-lock.json

npm ERR! npm ci can only install packages when your package.json and package-lock.json or npm-shrinkwrap.json are in sync. Please update your lock file with npm install before continuing.