Load to nozzle: Fix too short purge distance

PFW-1506

Change in memory:
Flash: +8 bytes
SRAM: 0 bytes

Firmware/ultralcd.cpp

@@ -4775,6 +4775,11 @@ static void mmu_load_filament_menu() {
 static inline void lcd_mmu_load_to_nozzle_wrapper(uint8_t index){
     MMU2::mmu2.load_filament_to_nozzle(index);
 
+    // Extrude a little bit of filament so the user
+    // can see the color is correct
+    load_filament_final_feed();
+    st_synchronize();
+
     // Ask user if the extruded color is correct:
     lcd_return_to_status();
     lcd_load_filament_color_check();