Update app.py

fix typo in code input

app.py

@@ -38,7 +38,7 @@ flipped = img.transpose(Image.FLIP_LEFT_RIGHT)
 
 # Save output
 # flipped.save(os.path.join(output_path, "flipped.png"))
-flipped.save()"flipped.png")
+flipped.save("flipped.png")
 print("Image flipped and saved as flipped.png.")
 """