[improve][io] Set default connector class for debezium connectors

[jiangpengcheng]

Fixes #25214

Motivation

Debezium connectors need to set the connector.class config manually, which is unnecessary

Modifications

Make Debezium connectors set connector.class automatically.

Verifying this change

• Make sure that the change passes the CI checks.

This change is already covered by existing tests, under package:

• org.apache.pulsar.tests.integration.io.sources.debezium.

Does this pull request potentially affect one of the following parts:

If the box was checked, please highlight the changes

• Dependencies (add or upgrade a dependency)
• The public API
• The schema
• The default values of configurations
  • debezium connectors will set the connector.class automatically
• The threading model
• The binary protocol
• The REST endpoints
• The admin CLI options
• The metrics
• Anything that affects deployment

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository: jiangpengcheng#49

[lhotari]

LGTM

[lhotari]

/pulsarbot rerun-failure-checks