ci: make ci happy lint the code, delete unused imports

Signed-off-by: yihong0618 <zouzou0208@gmail.com>

examples/gradio_test.py

@@ -3,17 +3,19 @@
 
 import gradio as gr
 
+
 def change_tab():
     return gr.Tabs.update(selected=1)
 
+
 with gr.Blocks() as demo:
     with gr.Tabs() as tabs:
         with gr.TabItem("Train", id=0):
             t = gr.Textbox()
         with gr.TabItem("Inference", id=1):
             i = gr.Image()
-    
+
     btn = gr.Button()
     btn.click(change_tab, None, tabs)
 
-demo.launch()
+demo.launch()