Tweak serial output code

Marlin/src/module/endstops.cpp

@@ -872,7 +872,7 @@ void Endstops::update() {
       #if HAS_Z3_MAX
         ES_REPORT_CHANGE(Z3_MAX);
       #endif
-      SERIAL_ECHOPGM("\n\n");
+      SERIAL_ECHOLNPGM("\n");
       analogWrite(LED_PIN, local_LED_status);
       local_LED_status ^= 255;
       old_live_state_local = live_state_local;