[Improvement] Split spark connector with different Scala version

### What would you like to be improved?

Currently, we can only use one scala version in a build process, say 2.12 or 2.13, we need to support them both in a single build task.

### How should we improve?

_No response_

Start by locating the Spark connector build configuration and the declarations that select Scala 2.12 or 2.13. Determine how a single build task could support both versions, then verify that each connector variant builds successfully under the intended Scala versions.

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