fix typo

app.py

@@ -52,7 +52,7 @@ with gr.Blocks() as demo:
                         visible=False
                     )
                     
-                    def update_visability(radio_value):
+                    def update_visibility(radio_value):
                         return { 
                             watermark_image: 
                                 { 
@@ -72,7 +72,7 @@ with gr.Blocks() as demo:
                             }
 
             with gr.Column():
-                gr.Markdown("### Appied watermark image")
+                gr.Markdown("### Applied watermark image")
                 output_image = gr.Image(show_label=False)
         with gr.Row():
             apply_button =gr.Button("Apply")
@@ -88,7 +88,7 @@ with gr.Blocks() as demo:
         extract_button = gr.Button("Extract")
     
     radio_button.change(
-        fn=update_visability, 
+        fn=update_visibility, 
         inputs=radio_button,
         outputs=[watermark_image, watermark_text, watermark_url]
     )