[16.0][FIX] document_page_tag: Use api.model_create_multi

   Using decorator api.model_create_multi for create
method in document_page_tag model

document_page_tag/models/document_page_tag.py

@@ -15,10 +15,11 @@ class DocumentPageTag(models.Model):
         ("unique_name", "unique(name)", "Tags must be unique"),
     ]
 
-    @api.model
-    def create(self, vals):
+    @api.model_create_multi
+    def create(self, vals_list):
         """Be nice when trying to create duplicates"""
-        existing = self.search([("name", "=ilike", vals["name"])], limit=1)
-        if existing:
-            return existing
-        return super().create(vals)
+        for vals in vals_list:
+           existing = self.search([("name", "=ilike", vals["name"])], limit=1)
+           if existing:
+              return existing
+        return super().create(vals_list)