- switched to using the Testcontainers implementation for Confluent Kafka. This required some changes in the tests setup.
- This also exposed an issue where the CommonClientPropertiesBuilder being an object was causing it to be shared across tests, which while cannot be an issue in main code, it still is more correct for it to be a class.

fix for this error:
```
Run RELEASE_TYPE="snapshot"
🔄 Creating snapshot version
Final version:
Project version: 2.2.3-SNAPSHOT
Error: Unable to process file command 'output' successfully.
Error: Invalid format 'Project version: 2.2.3-SNAPSHOT'
```

fix for this error:
```
Run RELEASE_TYPE="snapshot"
🔄 Creating snapshot version
Final version:
Project version: 2.2.3-SNAPSHOT
Error: Unable to process file command 'output' successfully.
Error: Invalid format 'Project version: 2.2.3-SNAPSHOT'
```