Add support for AWS transcribe

[saharmor]

see https://docs.aws.amazon.com/transcribe/latest/dg/streaming.html
https://aws.amazon.com/blogs/developer/transcribe-streaming-sdk-for-python-preview/

[saharmor]

Also, https://github.com/awslabs/amazon-transcribe-streaming-sdk
https://github.com/gabrielmartinigit/aws-realtime-transcription/blob/main/backend/app.py