abstract pubsub service via gocloud

[pxp928]

Description of the PR

Utilizing gocloud we can abstract out the pubsub used within GUAC. By default, it does still work with NATS Jetstream but now has the ability for other cloud provider/third-party pubsub services to be used (such as AWS, GCP, Azure. NATS, Kafka and RabbitMQ.

I tested it with AWS S3 as the blob store and AWS SQS as the pubsub with authentication handled via AWS CLI:

go run ./cmd/guacingest --blob-addr "s3://test?region=us-east-2" --pubsub-addr "awssqs://sqs.us-east-2.amazonaws.com/123456789012/myqueue?region=us-east-2"

and in another terminal:

go run ./cmd/guaccollect files --blob-addr "s3://test?region=us-east-2" --pubsub-addr "awssqs://sqs.us-east-2.amazonaws.com/123456789012/myqueue?region=us-east-2" ../guac-data/docs

Also fixes #765

Also addressed issue #460 with the addition of sending CDEvents via the pubsub

PR Checklist

• All commits have a Developer Certificate of Origin (DCO) -- they are generated using -s flag to git commit.
• All new changes are covered by tests
• If GraphQL schema is changed, make generate has been run
• If collectsub protobuf has been changed, make proto has been run
• All CI checks are passing (tests and formatting)
• All dependent PRs have already been merged

[jeffmendoza]

Should figure out the TODO and commented out code before merging probably.

[pxp928]

Should figure out the TODO and commented out code before merging probably.

Removed the commented out code as we are not using it.