Add translations to the demo server

[giovramirez]

Hi @michaelbromley

From vendure-ecommerce/storefront-qwik-starter#91 (comment)

I can think of these steps to add Spanish translations to the demo server. They will be implemented in the script https://github.com/vendure-ecommerce/vendure-demo/blob/master/src/reset-server.ts

Please let me know your thoughts!

1. Global config

Add the new language to the Vendure server. So we need to send to the GlobalSettingsService.updateSettings service the availableLanguages the array ["en", "es"]

2. Products

Get all products created by the populate function and for each one:

2.1 Add to the translations array the translation to Spanish.
2.2 Call ProductDetailService.updateProduct.

3. Collections

Get all collections created by the populate function and for each one:

3.1 Add to the translations array the translation to Spanish.
3.2 Call CollectionService.update.

Questions

1. Should we keep the same slugs for es and en languages?