refactor: improve knowledge editing logic to prevent name duplication

--bug=1057801 --user=刘瑞斌 【知识库】不同文件夹下创建相同名称的知识库成功，当切换知识库向量模型时会提示知识库名称重复 https://www.tapd.cn/62980211/s/1721429

Author: liuruibin

apps/knowledge/serializers/knowledge.py

@@ -325,13 +325,13 @@ def one(self):
         @transaction.atomic
         def edit(self, instance: Dict):
             self.is_valid()
+            knowledge = QuerySet(Knowledge).get(id=self.data.get("knowledge_id"))
             if QuerySet(Knowledge).filter(
-                    workspace_id=self.data.get('workspace_id'),
+                    workspace_id=knowledge.workspace_id,
                     name=instance.get('name'),
-                    folder_id=instance.get('folder_id', self.data.get('workspace_id'))
-            ).exclude(id=self.data.get('knowledge_id')).exists():
+                    folder_id=knowledge.folder_id
+            ).exclude(id=knowledge.id).exists():
                 raise AppApiException(500, _('Knowledge base name duplicate!'))
-            knowledge = QuerySet(Knowledge).get(id=self.data.get("knowledge_id"))
             KnowledgeEditRequest(data=instance).is_valid(knowledge=knowledge)
             if 'embedding_model_id' in instance:
                 knowledge.embedding_model_id = instance.get('embedding_model_id')