Method dwell

Marlin/src/gcode/gcode.cpp:248–251

* Dwell waits immediately. It does not synchronize. */

 * Dwell waits immediately. It does not synchronize.
 */
void GcodeSuite::dwell(const millis_t time) {
  const millis_t start_ms = millis();
  while (PENDING(millis(), start_ms, time)) idle();
}

/**
 * When G29_RETRY_AND_RECOVER is enabled, call G29() in