fixed share write permission for meal plan

cookbook/views/api.py

@@ -107,6 +107,7 @@ class ExtendedRecipeMixin():
     '''
     ExtendedRecipe annotates a queryset with recipe_image and recipe_count values
     '''
+
     @classmethod
     def annotate_recipe(self, queryset=None, request=None, serializer=None, tree=False):
         extended = str2bool(request.query_params.get('extended', None))
@@ -540,7 +541,7 @@ class MealPlanViewSet(viewsets.ModelViewSet):
     """
     queryset = MealPlan.objects
     serializer_class = MealPlanSerializer
-    permission_classes = [CustomIsOwner]
+    permission_classes = [CustomIsOwner | CustomIsShared]
 
     def get_queryset(self):
         queryset = self.queryset.filter(