chore: cleanup ruff flake8-simplify linter rules (#8286)

Co-authored-by: -LAN- <laipz8200@outlook.com>

api/core/tools/provider/builtin/stablediffusion/tools/stable_diffusion.py

@@ -206,10 +206,9 @@ class StableDiffusionTool(BuiltinTool):
 
         # Convert image to RGB and save as PNG
         try:
-            with Image.open(io.BytesIO(image_binary)) as image:
-                with io.BytesIO() as buffer:
-                    image.convert("RGB").save(buffer, format="PNG")
-                    image_binary = buffer.getvalue()
+            with Image.open(io.BytesIO(image_binary)) as image, io.BytesIO() as buffer:
+                image.convert("RGB").save(buffer, format="PNG")
+                image_binary = buffer.getvalue()
         except Exception as e:
             return self.create_text_message(f"Failed to process the image: {str(e)}")