Do not call teardown or async_teardown

[vinniefalco]

teardown and async_teardown are called automatically as part of the WebSocket close procedure, there is no need to invoke them manually:

scio-beast/src/scio_beast.hpp

Line 599 in 65ebee2

// :TODO: we shoudl be using teardown? http://vinniefalco.github.io/beast/beast/ref/beast__websocket__async_teardown/overload2.html

If you implement your own socket class, and you want it to work with beast::websocket::stream then you will need to provide overloads of teardown and async_teardown which will be called as needed to perform the WebSocket close.

[NuSkooler]

@vinniefalco Thanks!