Move DLT pipeline integration test to Workflows

[cs23andris]

• Each pipeline should have a corresponding integration test job with tasks: setup, run DLT pipeline, validate
• The integration test job should be running on serverless
• There should be a runner job that executes all integration test jobs
• This runner job should be triggered by the build pipeline
• In this case running the validate pipeline step is unnecessary as the whole pipeline is executed in the integration test