proto: disallow client streaming apis

Some environments have difficultly supporting client streaming apis (eg
grpc-web) and as such we should disallow these in order to be able to
support the most number of clients possible.

crates/sui-rpc-api/buf.yaml

@@ -7,6 +7,9 @@ modules:
     lint:
       use:
         - STANDARD
+        # Disallow client streaming apis since many clients (eg grpc-web)
+        # cannot properly handle client side streaming requests.
+        - RPC_NO_CLIENT_STREAMING
       ignore_only:
         PACKAGE_VERSION_SUFFIX:
           - proto/sui.types.proto