[FIX] check mp_dirty to avoid repeated rendering

The patch fixes the issue related to repeated orderline rerendering. It means
that if products of the order were printed before, those will not be rendered
again when new updates of order is sent to the kitchen.

Closes #28577

addons/pos_restaurant/static/src/js/multiprint.js

@@ -137,8 +137,10 @@ models.Orderline = models.Orderline.extend({
         }
     },
     set_dirty: function(dirty) {
-        this.mp_dirty = dirty;
-        this.trigger('change',this);
+        if (this.mp_dirty !== dirty) {
+            this.mp_dirty = dirty;
+            this.trigger('change', this);
+        }
     },
     get_line_diff_hash: function(){
         if (this.get_note()) {