[Grpc call objects](https://grpc.github.io/grpc/python/grpc.html?highlight=channelconnectivity#grpc.StreamUnaryMultiCallable) accept a [grpc.Compression](https://grpc.github.io/grpc/python/grpc.html?highlight=channelconnectivity#grpc.Compression) We should allow passing this parameter to all api calls in the generated library, as well as on channel creation. Duplicate of: https://github.com/googleapis/gapic-generator-python/issues/1310
Grpc call objects accept a grpc.Compression
We should allow passing this parameter to all api calls in the generated library, as well as on channel creation.
Duplicate of: googleapis/gapic-generator-python#1310