debug output before sleep

src/main.cpp

@@ -327,6 +327,8 @@ void suspend(uint32_t secondsToSleep) {
   //properly disconnect from the MQTT broker
   iot.mqtt.disconnect();
 
+  Serial.printf("going to deep_sleep for %u seconds", secondsToSleep);
+
   esp_sleep_enable_timer_wakeup(1000000LL * secondsToSleep);
   const uint64_t ext_wakeup_rotarybtn_mask = 1ULL << rotaryPinButton;
 //  const uint64_t ext_wakeup_sensor_mask = 1ULL << sensorPin;