fix nosuch file error

app_gfp.py

@@ -19,6 +19,8 @@ if not os.path.exists('RestoreFormer.pth'):
 if not os.path.exists('CodeFormer.pth'):
     os.system("wget https://github.com/TencentARC/GFPGAN/releases/download/v1.3.4/CodeFormer.pth -P .")
 
+os.makedirs('output', exist_ok=True)
+
 @spaces.GPU(duration=10)
 def enhance(
     img_path:str,