fixup! Replace check() override with update connectionState override

Author: andreagilardoni

src/GenericConnectionHandler.h

@@ -38,8 +38,6 @@ class GenericConnectionHandler : public ConnectionHandler
 
     GenericConnectionHandler(bool const keep_alive=true): ConnectionHandler(keep_alive), _ch(nullptr) {}
 
-    // NetworkConnectionState check() override;
-
     #if defined(BOARD_HAS_NOTECARD) || defined(BOARD_HAS_LORA)
       virtual bool available() = 0;
       virtual int read() = 0;