Add HealthCheck wait for KafkaConnect (#2449)

[shubhwip]

• Remove hardcoded port for Schema Registry
• closes #2449

• [ ] Breaking change? (if so, please describe the impact and migration path for existing application instances)

What changes did you make? (Give an overview) I have updated the Wait strategy of Kafka Connect container from path based to healthchecks based. Also removed an hardcoded port used in Schema registry container constructor call.

Is there anything you'd like reviewers to focus on?

How Has This Been Tested? (put an "x" (case-sensitive!) next to an item)

• [ ] No need to
• [x] Manually (please, describe, if necessary)
• [ ] Unit checks
• [ ] Integration checks
• [x] Covered by existing automation

Checklist (put an "x" (case-sensitive!) next to all the items, otherwise the build will fail)

• [x] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation (e.g. ENVIRONMENT VARIABLES)
• [ ] My changes generate no new warnings (e.g. Sonar is happy)
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes
• [ ] Any dependent changes have been merged

Check out Contributing and Code of Conduct

A picture of a cute animal (not mandatory but encouraged)