Enable ZeroGPU queue (beta feature)

Instead of the "No GPU is currently available" error, visitors should see a "Waiting for a GPU to become available" message if not GPU is available at the moment

app.py

@@ -16,7 +16,7 @@ pipe = pipe.to("cuda")
 pipe.enable_model_cpu_offload() 
 pipe.enable_vae_slicing()
 
-@spaces.GPU
+@spaces.GPU(enable_queue=True)
 def infer(prompt):
     print(f"""
     —/n