examples: introduce LaunchPad in strapi (#73244)
## Description
The previous
[nextjs-corporate-starter](https://github.com/strapi/nextjs-corporate-starter)
has been archived.
With the release of Strapi 5, launched an even more awesome demo/starter
project called [LaunchPad](https://github.com/strapi/LaunchPad).
You can learn more about the LaunchPad app from [the
blog](https://strapi.io/blog/launchpad-demo-app).
In addition, update
[.gitignore](https://github.com/vercel/next.js/blob/canary/examples/cms-strapi/.gitignore).
CC: @samcx
### Adding or Updating Examples
- [x] The "examples guidelines" are followed from our contributing doc
https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md
- [x] Make sure the linting passes by running `pnpm build && pnpm lint`.
See
https://github.com/vercel/next.js/blob/canary/contributing/repository/linting.md
Co-authored-by: Sam Ko <sam@vercel.com>
