Enable swagger behind proxy

[fjugipe]

Description

After this pull request:

• Swagger documentation is directed to the correct path and is able to get the openapi.json
• Using the API queries via Swagger execute will be correctly directed to the proxys url

Features

• Add x-forwarded-headers middleware to handle the requests with known proxies
  • Using the instructions on https://github.com/EUMETNET/uvicorn-middleware-forwarded-host
• Add UvicornWorkerWithForwardedHeaders uvicorn worker to disable default proxy header handling with gunicorn
  • gunicorn does not have --proxy-headers option in startup like uvicorn does

    --proxy-headers / --no-proxy-headers
                                  Enable/Disable X-Forwarded-Proto,
                                  X-Forwarded-For, X-Forwarded-Port to
                                  populate remote address info.
  

closes #290

[github-actions]

Title	Coverage	Tests	Skipped	Failures	Errors	Time
API Unit Tests		47	0 💤	0 ❌	0 🔥	1.641s ⏱️
Ingest Unit Tests		16	0 💤	0 ❌	0 🔥	2.484s ⏱️

[Teddy-1000]

LGTM