[HUDI-7229] support partial updates for cdc payload demo

[linliu-code]

Change Logs

Use MysqlDebeziumSource as an example to demonstrate the design.

Impact

Low.

Risk level (write none, low medium or high below)

None, just a demo.

Contributor's checklist

• [ ] Read through contributor's guide
• [ ] Change Logs and Impact were stated clearly
• [ ] Adequate tests were added if applicable
• [ ] CI passed

[hudi-bot]

CI report:

• dc3cdf3ad2ea6666994be78af843c17a74ccacf1 Azure: FAILURE

Bot commands

@hudi-bot supports the following commands:

• @hudi-bot run azure re-run the last Azure build

[linliu-code]

This is not a correct direction for cdc demo.