examples: remove app-dir in i18n-routing directory name

[JamBalaya56562]

What?

1. Rename app-dir-i18n-routing example i18n-routing.
2. Rename i18n-routing example i18n-routing-pages.
3. Update the docs mentions i18n-routing examples.
4. Update the test includes i18n-routing examples.

Why?

The default has already been App Router anyways and a lot of examples have migrated over.
x-ref: #72642 (comment)

How?

Change them as in reproduction-template and reproduction-template-pages examples.

Improving Documentation

• Run pnpm prettier-fix to fix formatting issues before opening the PR.
• Read the Docs Contribution Guide to ensure your contribution follows the docs guidelines: https://nextjs.org/docs/community/contribution-guide

Adding or Updating Examples

• The "examples guidelines" are followed from our contributing doc https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md
• Make sure the linting passes by running pnpm build && pnpm lint. See https://github.com/vercel/next.js/blob/canary/contributing/repository/linting.md

[ijjk]

Allow CI Workflow Run

• approve CI run for commit: 41c6060

Note: this should only be enabled once the PR is ready to go and can only be enabled by a maintainer

[delbaoliveira]

Ty! FYI @samcx

[MonstraG]

Forgot to update docs:
https://nextjs.org/docs/app/building-your-application/routing/internationalization

still links to app-dir-i18n-routing

[JamBalaya56562]

Forgot to update docs: https://nextjs.org/docs/app/building-your-application/routing/internationalization

still links to app-dir-i18n-routing

Thank you for your checking!
Yeah, v15.0.4 stable document has an old link.

However, the canary documentation shows the correct new link.

In conclusion, I didn't forget to update the internationalization document.