Handle a case when spind doesn't return results

pyzebra/app/panel_spind.py

@@ -73,8 +73,11 @@ def create():
                 check=True,
             )
 
+            try:
                 with open(os.path.join(temp_dir, "spind.txt")) as f_out:
                     output_textarea.value = f_out.readlines()
+            except FileNotFoundError:
+                print("No results from spind")
 
     process_button = Button(label="Process", button_type="primary")
     process_button.on_click(process_button_callback)