Support additional WDS_SOCKET_* options

Created by: ruckc

Is your proposal related to a problem?

I am always frustrated with the limited pass through of WDS_SOCKET_ variables. Ideally I wish there was a WDS_SOCKET_URL={url} and potentially WDS_SOCKET_PROTOCOL.

Describe the solution you'd like

Expand the logic in websocketDevServer.config.js to support alternative options from webpack-dev-server, such as webSocketURL: ${WDS_SOCKET_URL} and the protocol options in the object notation.

Describe alternatives you've considered

Ejecting is the only viable solution currently given the hardcoded nature of the current WDS_SOCKET variable support.

Additional context

This would be useful for me when running the CRA/WDS behind a local reverse proxy in a development mode. I can't use the WDS's proxy values due to the applications requiring mutual-TLS authentication, hence the reverse proxy.