AP-1574 attempted fix to hanging consumer

[Samira-El]

Problem

Kafka consumer hangs at the end of sync and tap remains in running state without doing anything.

Proposed changes

Attempted fixes:

• Explicitly close the consumer. https://github.com/confluentinc/librdkafka/blob/master/INTRODUCTION.md#high-level-kafkaconsumer
• Commit offsets synchronously which is more reliable and makes the tap fail fast if cannot commit.

Types of changes

What types of changes does your code introduce to PipelineWise?
Put an x in the boxes that apply

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

• Description above provides context of the change
• I have added tests that prove my fix is effective or that my feature works
• Unit tests for changes (not needed for documentation changes)
• CI checks pass with my changes
• Bumping version in setup.py is an individual PR and not mixed with feature or bugfix PRs
• Commit message/PR title starts with [AP-NNNN] (if applicable. AP-NNNN = JIRA ID)
• Branch name starts with AP-NNN (if applicable. AP-NNN = JIRA ID)
• Commits follow "How to write a good git commit message"
• Relevant documentation is updated including usage instructions