remove debug file

demo/gradio/fast_api_demo.py

@@ -1,12 +0,0 @@
-from fastapi import FastAPI
-import gradio as gr
-
-app = FastAPI()
-
-def greet(name):
-    return f"Hello, {name}!"
-    
-gradio_interface = gr.Interface(fn=greet, inputs="text", outputs="text")
-gradio_app = gr.routes.App.create_app(gradio_interface)
-
-app.mount("/gradio", gradio_app)