Broken Self Hosted -> Configure services link and add Sites card to Self Hosting page

[crweiner]

💭 Description

I stumbled upon broken links to "Configure services" under Docs -> Advanced -> Self Hosting -> Platforms -> [Platform Name] that were pointing to /docs/advanced/self-hosting/configuration.

However, it looks like the [...]/configuration page no lonner exists, and is instead a heading under the Self Hosting page.

I'll soon submit a PR to fix the links to /docs/advanced/self-hosting#configuration instead.

I also noted that Appwrite Sites is not listed in the Configuration cards, so I added it, as that's one of my favorite new features! 😄

👀 Have you spent some time to check if this issue has been raised before?

• I checked and didn't find similar issue

🏢 Have you read the Code of Conduct?

• I have read the Code of Conduct

[crweiner]

PR added in #2499