[DEPRIORITISED] update docs to add link to redoc

[suzinyou]

Reviewer: @amiraliemami
Estimate: 10 mins

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Ticket

Fixes: None

Description

Goal

Link to redoc page for API docs, unless the guide is for testing the APIs. (Swagger UI allows for testing APIs, redoc doesn't)

Changes

1. Add link to deployed docs on OpenAPI page description
2. Switch top-level "API docs" link to redoc page
3. Added/switched to redoc links in docs where appropriate

Future Tasks

Remove Swagger UI screenshots in docs website. (ticket)

How has this been tested?

1. Run python core_backend/main.py, check HTTP://localhost:8000/redoc and /docs.
2. Run mkdocs serve -a localhost:8080 and check docs

To-do before merge (optional)

Checklist

Fill with x for completed.

• My code follows the style guidelines of this project
• I have reviewed my own code to ensure good quality
• I have tested the functionality of my code to ensure it works as intended
• I have resolved merge conflicts
• I have updated affected documentation