Use maven plugin to generate Client-Side CAB proto code.

[huangjiahua]

Use the protobuf-maven-plugin to automatically generate the protobuf Java code and remove the generated code.

The version of protoc is determined by the project.protobuf.version and it's currently 3.25.5.

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Change-Id: I8154ea3c3c3126a1cf47e563b9b9e2f6b85c7f1a

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• [ ] Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea
• [ ] Ensure the tests and linter pass
• [ ] Code coverage does not decrease (if any source code was changed)
• [ ] Appropriate docs were updated (if necessary)

Fixes #<issue_number_goes_here> ☕️

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