AIOHTTP websocket messages of type "ERROR" not handled correctly

[DoctorJohn]

Describe the Bug

Both our AIOHTTP implementations of the WS subprotocols currently don't handle AIOHTTP WS messages of type "ERROR" correctly:

• Our implementation of the legacy WS subprotocol ignores messages of type ERROR (ref)
• Our implementation of the newer WS subprotocol complains that it's not a TEXT message and closes the connection (ref)

Instead, both implementations should return an error to the client and close the connection.

[DoctorJohn]

Merging #3638 already solved this issue.

AIOHTTP closes the WebSocket internally with code 1006 (Abnormal Closure) before yielding a message of type "ERROR." Our WebSocket integration code recognizes that the WebSocket has been closed and gracefully stops. Before said PR was merged, our AIOHTTP integration would try to close the WebSocket again because a non-text message (i.e., the message of type "ERROR") was received.