[Docs]: Add doc to deploy appsmith using terraform

### Problem Statement

Currently we have various ways to deploy Appsmith and they follow certain sequence of steps to deploy appsmith.
With **[appsmith-tf-modules](https://github.com/appsmithorg/appsmith-tf-modules)** .

User can deploy appsmith using terraform following this [doc](https://github.com/appsmithorg/appsmith-tf-modules/blob/main/README.md)

### Use Cases / User query reference

One more section under self hosting called terraform modules and adding the above steps to deploy appsmith

Video and thread
https://theappsmith.slack.com/archives/C02MUD8DNUR/p1718804379673859

### Audio/Video Recording

_No response_

### Product Requirements Document

_No response_

### Other Relevant Links

_No response_

### Checklist

- [X] Reviewed existing documentation to ensure this request is not duplicated.
- [X] Attached relevant media or supporting materials like links to the PRD, feature recordings, Slack or Discord links, and any other relevant resources.