add a way to get out of test mode

src/Keyboardio-Model01-TestMode.cpp

@@ -79,6 +79,9 @@ void TestMode_::test_matrix () {
     LEDControl.set_all_leds_to(50,0,0);
     while(1) {
         KeyboardHardware.read_matrix();
+    	if (KeyboardHardware.leftHandState.all == (R0C0 | R0C6 | R3C6 ) {
+		break;
+	}
         for (byte row = 0; row < 4; row++) {
             for (byte col = 0; col < 8; col++) {