Dselans/streamdal integration

[dselans]

DO NOT MERGE UNTIL GO-SDK PR IS MERGED AND A NEW SDK RELEASE IS MADE

streamdal/streamdal#295

This integrates streamdal's Go SDK into Kafka and GCP-PubSub.

You enable it by passing a few streamdal flags via manage:

plumber manage create relay kafka \
  --connection-id 3bfd8126-a32f-43ed-a89d-94e616d9b7ea \
  --use-consumer-group \
  --topics test \
  --collection-token 3831a9fb-4117-4599-b834-04d47341b491 \
  --streamdal-integration-enable \
  --streamdal-integration-service-name plumber

The SDK is instantiated per relay.

Tested it w/ Kafka.

I had to update vendor because SDK introduced a bunch of new libs - I tested relay create/delete/stop/resume - everything seems to work right.