Add maxcompute batch predictor (#626)

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# Description
* This PR adds MaxCompute as a source and sink to batch prediction jobs.
This allows users to perform batch prediction on data stored in
MaxCompute and write the results back into MaxCompute.

# Modifications
* `python/batch-predictor` 
  * `merlinpyspark` package source code modified
  * Added missing proto spec for PredictionJob protobuf
  * Added MaxCompute Jar dependencies to base.Dockerfile
* `python/sdk`
* Modified python sdk to include MaxComputeSource and MaxComputeSink
classes
  * Modified swagger.yaml and regenerated python and go clients
  * Will add tests and readme in separate MR

# Tests
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- [ ] Deploying PyFunc models
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# Checklist
- [x] Added PR label
- [ ] Added unit test, integration, and/or e2e tests
- [x] Tested locally
- [ ] Updated documentation
- [x] Update Swagger spec if the PR introduce API changes
- [x] Regenerated Golang and Python client if the PR introduces API
changes

# Release Notes
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```release-note
- Support MaxCompute source and sink for batch prediction jobs
```

Author: shydefoo