Enhance documentation/API documentation and examples

[nifedara]

What type of PR is this?

• [ ] 📝 Documentation

Related Issue :

• #219

What does this PR do?

• Makes updates to Auth, Extract, Tasks, Custom Exports, Stats, HDX and S3 endpoints

• Adds top-level security

• Adds API description

• Adds endpoints description

• Adds path and query parameters description

• Adds an error message model

• Updates the HTTPException response to match the error model

• Adds 200, 401, 403, 404, 429, & 500 responses and examples to endpoints

• Removes trailing slashes from endpoints

Consideration :

• The top-level security will save users from repeatedly entering the access code for every protected endpoint
• Having parameters defined helps the users understand the API better.
• The error model helps maintain the consistency of error that the user expects and it is also recommended for API security that response schemas be used hence why I added a model for Error messages.
• Removing the trailing slashes is good practice that ensures consistency in the endpoints
• I was proactive in getting the responses from each endpoint.
• Increases the API score from 54 to 69. I still intend to improve it more.

How to test?

• Clone this repo
• Follow Docker Installation Guide or local installation guide
• Shoot the server up and view the Documentation changes on your localhost

Screenshots :

Before:

After my changes:

Checklists:

Checklist before requesting a review :

• 📖 Read the HOT Code of Conduct: https://docs.hotosm.org/code-of-conduct
• 👷‍♀️ Create small PRs. In most cases, this will be possible.
• ✅ Provide tests for your changes.
• 📝 Use descriptive commit messages.
• 📗 Update any related documentation and include any relevant screenshots.

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