Encountered change event for table databasename.tablename whose schema isn`t known to this connector

**BUG REPORT**


When the standalone mode is started, if the runtime has a json configuration file other than the position.json related files, it will cause the debezium source to start an error.


At present, it can be solved by deleting files other than position and restarting the runtime.

1. Please describe the issue you observed:

- What did you do (The steps to reproduce)?

- What is expected to see?

- What did you see instead?

2. Please tell us about your environment:

3. Other information (e.g. detailed explanation, logs, related issues, suggestions on how to fix, etc):

**FEATURE REQUEST**

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