Add support custom domain for S3 storage
Related issue: N/A
This merge request will gives availability to server owner who using S3 as a CDN, without proxying files to server.
It will helps reducing traffic for server, and also improves file transfer speed for users.
Here is original document about environment variable what I inserted:
This Merge Request includes:
- A changelog fragment (cf https://docs.funkwhale.audio/contributing.html#changelog-management)