Update German language (#13012)

Marlin/src/lcd/language/language_de.h

 #define MSG_PREHEAT_2_SETTINGS              _UxGT("Vorw. " PREHEAT_2_LABEL " Einst.")
 #define MSG_PREHEAT_CUSTOM                  _UxGT("benutzerdef. Heizen")
 #define MSG_COOLDOWN                        _UxGT("Abkühlen")
+#define MSG_LASER_MENU                      _UxGT("Laser")
+#define MSG_LASER_OFF                       _UxGT("Laser aus")
+#define MSG_LASER_ON                        _UxGT("Laser an")
+#define MSG_LASER_POWER                     _UxGT("Laserleistung")
+#define MSG_SPINDLE_REVERSE                 _UxGT("Spindelrichtung")
 #define MSG_SWITCH_PS_ON                    _UxGT("Netzteil ein")
 #define MSG_SWITCH_PS_OFF                   _UxGT("Netzteil aus")
 #define MSG_EXTRUDE                         _UxGT("Extrudieren")
 #define MSG_TOOL_CHANGE_ZLIFT               _UxGT("Z anheben")
 #define MSG_SINGLENOZZLE_PRIME_SPD          _UxGT("Prime-Geschwin.")
 #define MSG_SINGLENOZZLE_RETRACT_SPD        _UxGT("Rückzug-Geschwin.")
+#define MSG_NOZZLE_STANDBY                  _UxGT("Düsen-Standby")
 #define MSG_FILAMENTCHANGE                  _UxGT("Filament wechseln")
 #define MSG_FILAMENTLOAD                    _UxGT("Filament laden")
 #define MSG_FILAMENTUNLOAD                  _UxGT("Filament entladen")