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**What this PR does / why we need it**:
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Starting version 1.49.0, grpc uses protobuf version 4.X which is
incompatible with most of our dependencies
(grpc/grpc#30805) . This causes error while
building Pyfunc model:
```
ImportError: cannot import name 'builder' from 'google.protobuf.internal' (/Users/aria/.local/share/virtualenvs/pyfunc-server-sOMOjTdZ/lib/python3.7/site-packages/google/protobuf/internal/__init__.py)
```


**Does this PR introduce a user-facing change?**:
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NONE

**Checklist**

- [N.A.] Added unit test, integration, and/or e2e tests
- [x] Tested locally
- [N.A.] Updated documentation
- [N.A.] Update Swagger spec if the PR introduce API changes
- [N.A.] Regenerated Golang and Python client if the PR introduce API
changes