Add support to ChatGPT plugin

[tfius]

To be able to use FairOS with ChatGPT comming plugins. We can extend FairOS.

• we need yaml that can be accessed from domain (https://gist.github.com/asabya/c7fe0afdac17172e44629182ab861df4)
• logo that can be accessed from domain
• README.md accessed from domain

contents of ai-plugin.json:

{
    "schema_version": "v1",
    "name_for_model": "FairOs retrieval",
    "name_for_human": "FairOS retrival plugin",
    "description_for_model": "Plugin for searching through the user's documents to find answers to questions and retrieve relevant information. Use it whenever a user asks something that might be found in their personal information, or asks you to save information for later.",
    "description_for_human": "Search through your pods and documents and do whatever with your data.",
    "auth": {
      "type": "user_http",
      "authorization_type": "bearer"
    },
    "api": {
      "type": "openapi",
      "url": "https://fairos.fairdatasociety.org/.well-known/openapi.yaml",
      "has_user_authentication": false
    },
    "logo_url": "https://fairos.fairdatasociety.org/.well-known/logo.png",
    "contact_email": "hello@fairdatasociety.org", 
    "legal_info_url": "hello@legal.com"
}