s3_media_upload lacks ability to set region or endpoint_url

[console-cowboy]

At present, the synapse-s3-storage-provider toolkit has an uneven implementation of configuration options. s3_storage_provider.py permits the configuration of a custom endpoint URL and setting the region for sessions, but s3_media_upload does not support setting these as options.

[koehn]

I think you're supposed to set those using e.g., aws configure. See the boto config linked from the README.md