Remove openapi websocket classes

[niloc132]

With the rewrite to gRPC, we no longer need web-shared-beans and web-shared-socket, but these classes are still used from a few places. Any code that uses web-shared-socket no longer works, since the websocket itself was removed.

• c# is built from this, should all be deleted until the API is solidified in enterprise, and the gRPC api is solidified in open source. This doesn't work presently anyway.
• jupyter probably also makes sense to be deleted since it uses websockets not only for openapi but also for forwarding sockets, and that isn't rebuilt to work in envoy yet either.
• js api uses the web-shared-beans classes to manage state, and to simplify updating to gRPC many protobuf objects are being copied to the old beans before being exposed to JS.

[niloc132]

See also
#186
#188