Update grpc-java monorepo to v1.73.0 (minor)

This MR contains the following updates:

Package	Type	Update	Change
io.grpc:grpc-stub	dependencies	minor	1.72.0 -> 1.73.0
io.grpc:grpc-protobuf	dependencies	minor	1.72.0 -> 1.73.0
io.grpc:grpc-netty-shaded	dependencies	minor	1.72.0 -> 1.73.0
io.grpc:protoc-gen-grpc-java	dependencies	minor	1.72.0 -> 1.73.0

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