Add more warehouses to database permissions

[agnessnowplow]

What are you changing in this pull request and why?

The proposed changes are regarding this issue raised last week: #3901

It would be nice to have more warehouses within References / warehouse permissions with sample grants, this PR aims to follow the already existing Snowflake example and add Databricks, Redshift, and Postgres as well (skipping BigQuery due to their unique IAM access control management)

#Resolves #3824

Checklist

• Review the Content style guide and About versioning so my content adheres to these guidelines.
• Add a checklist item for anything that needs to happen before this PR is merged, such as "needs technical review" or "change base branch."

Adding new pages (delete if not applicable):

• Add page to website/sidebars.js

• Provide a unique filename for the new page

• Needs to have a technical review, at least to verify the proposed changes are correct and possibly expand with other examples.

• Tested it locally (npm run)

[welcome]

Hello!👋 Thanks for contributing to the dbt product documentation and opening this pull request! ✨
We use Markdown and some HTML to write the dbt product documentation. When writing content, you can use our style guide and content types to understand our writing standards and how we organize information in the dbt product docs.
We'll review your contribution and respond as soon as we can. 😄

[netlify]

✅ Deploy Preview for docs-getdbt-com ready!

Name	Link
🔨 Latest commit	ea1fab2
🔍 Latest deploy log	https://app.netlify.com/sites/docs-getdbt-com/deploys/64ef1197e3411300085d9a44
😎 Deploy Preview	https://deploy-preview-3943--docs-getdbt-com.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[rlh1994]

Hey @mirnawong1 is there anything we need to change to be able to get this merged please?

[vercel]

@mirnawong1 is attempting to deploy a commit to the dbt-labs Team on Vercel.

A member of the Team first needs to authorize it.

[mirnawong1]

this is so great @agnessnowplow and @rlh1994 ! thanks so much for opening this up and providing such diligent and detailed contributions 😍 ! apologies for the delay here and I'll review this right now - am going to loop in @dataders as well for his technical help - thank you for flagging @rlh1994 !

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Comments	Updated (UTC)
docs-getdbt-com	🛑 Canceled (Inspect)			Nov 1, 2023 6:21pm

[mirnawong1]

hey @agnessnowplow and @rlh1994 ! i think we're at a good place now and the deploy preview looks pretty great! i really appreciate you opening this wonderful pr and flagging this for us - this page needed some attention and thanks to your contribution, it now has much more info.

I'll get this merged for you but let me know if you have any questions or concerns