Use `instance_double` for stubbed websocket
Use `instance_double` for stubbed websocket

matrinox/appsignal-ruby,appsignal/appsignal-ruby,matrinox/appsignal-ruby,appsignal/appsignal,appsignal/appsignal-ruby,matrinox/appsignal-ruby,appsignal/appsignal,appsignal/appsignal-ruby,appsignal/appsignal-ruby