New docs section request: deployments

[devzom]

The Keystone docs are really extended and well developed but what's missing is the deployments section, taking into account a popular providers.
Thea question/request is based on the amount of repeating request to handle deployments on issues/bug section.

Will be great to provide a context of deploying as separate Keystone instance to some possible serverless providers and also as Docker instance.

V5 readmes:

• https://northflank.com/guides/deploy-keystonejs-on-northflank
• Render.yaml https://github.com/keystonejs/prisma-day-2021-workshop/blob/main/render.yaml
• Deploying Keystone to Heroku #2598

V6 readmes:

• https://github.com/keystonejs/keystone/tree/main/examples/framework-nextjs-pages-directory ( Deploy to Vercel button does trigger the vercel deployment but deploy fail, as GQL schema is outdated on init)
• https://keystonejs.com/blog/nextjs-keystone
• https://keystonejs.com/blog/embedded-mode-with-sqlite-nextjs#how-to-embed-keystone-sq-lite-in-a-next-js-app

YouTube resource:

• https://www.youtube.com/watch?v=Wq6eQVyW8ug&t=247s by @borisno2
  • GH repo with example of multizone next.js https://github.com/borisno2/on-the-hill-drama-club