will we have scala 2.12+ and spark 2.4.0+ support?

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### System Information
- **Spark or PySpark**: spark
- **SDK Version**: NA
- **Spark Version**: 2.4.4
- **Algorithm (e.g. KMeans)**:NA

### Describe the problem
Describe the problem or feature request clearly here.
Will we have scala 2.12 support?
I only see 2.11 exists.

for spark version I can find spark_2.4.0-1.4.2.dev0
when will we have none dev one?

Please share the road map if possible.

thank you

### Minimal repo / logs
Please provide any logs and a bare minimum reproducible test case, as this will be helpful to diagnose the problem. If including tracebacks, please include the full traceback. Large logs and files should be attached.

- **Exact command to reproduce**:

No files, tests, or entry points are named. Start by reviewing the repository's build and release configuration for the current Scala 2.11 and Spark 2.4.0 development artifact, then determine whether Scala 2.12 and a non-development Spark artifact are planned or technically supported. Done should be a documented support decision or a clearly scoped implementation plan.

Written by the indexing model from the issue text.