Summary:
This commit makes the websocket's delegate dispatch queue use `RCTWebSocketModule`'s method queue.
This fixes a bug where didReceiveMessage was called on the wrong queue, which is especially harmful if the websocket has a contentHandler expects to be running on the RCTWebSocketModule's method queue.
This also fixes the race condition where `_contentHandlers` and `_sockets` can be mutated from the main dispatch queue (the default in `RCTRSWebSocket`) and `RCTWebSocketModule`'s method queue.
Websockets still work, and hopefully crash less now.
- [iOS][BUGFIX][WebSocket] fix crashes caused by a race condition in websocket delegates.
Closes https://github.com/facebook/react-native/pull/18530
Differential Revision: D7394298
Pulled By: hramos
fbshipit-source-id: 230466ccb47ea532ced15cd7603256a19077b32b
228f5c83f9