New name for polymorphic executor. Trait for detecting new executors

test/beast/websocket/ping.cpp

@@ -378,7 +378,7 @@ public:
             using socket_type =
                 net::basic_stream_socket<
                     net::ip::tcp,
-                    net::executor>;
+                    net::any_io_executor>;
             net::io_context ioc;
             stream<socket_type> ws1(ioc);
             stream<socket_type> ws2(ioc);

test/beast/websocket/ssl.cpp

@@ -62,7 +62,7 @@ public:
             boost::asio::ssl::stream<
                 boost::asio::basic_stream_socket<
                     boost::asio::ip::tcp,
-                    boost::asio::executor>>>();
+                    net::any_io_executor>>>();
 
     }
 };