WebSocket: Support setting socket-specific certificates

[ADKaster]

The WebSocket IPC channel has had a set_certificates API since its inception, but it has never done anything but drop the user certificates on the floor. When connecting to a WebSocket URL, we always use the default certs that the WebSocket server process was started with.

[ADKaster]

Alternatively, if we don't want to support this use case, the IPC method should be removed