net.websocket: swap unsafe use of nil for a safe default value (#15836)

vlib/net/websocket/websocket_server.v

@@ -9,7 +9,9 @@ import rand
 // Server represents a websocket server connection
 pub struct Server {
 mut:
-	logger                  &log.Logger      = unsafe { nil } // logger used to log
+	logger &log.Logger = &log.Logger(&log.Log{
+	level: .info
+})
 	ls                      &net.TcpListener = unsafe { nil } // listener used to get incoming connection to socket
 	accept_client_callbacks []AcceptClientFn      // accept client callback functions
 	message_callbacks       []MessageEventHandler // new message callback functions