Document parameterized query support on gRPC clients

[jeffreyscarpenter]

The Java documentation does not describe how to do parameterized queries with the gRPC Java client. See stargate/stargate#2338 for sample code that could be useful.

The Rust documentation describes how to bind query values, but it might be good to indicate that this is how to support parameterized queries.

(The Node.js and Go client documentation do describe how to do parameterized queries.)