Issue webcompat#3380 - accepts list with 3 and 2 items tuples

Originally the list of tuples were 2 items long.
but the wizard is using in some cases 3 items long list (because of icons) for radio fields.

This leds to the duplication of the list of problem_choices with 2 items and 3 items. So instead of duplicating code, let's handle it in the function itself. There might be something more elegant to do. We can discover that later.

webcompat/form.py

@@ -329,6 +329,8 @@ def build_details(details):
 
 def get_radio_button_label(field_value, label_list):
     """Return human-readable label for problem choices form value."""
+    if len(label_list[0]) == 3:
+        label_list = [(value, text) for value, icon, text in label_list]
     for value, text in label_list:
         if value == field_value:
             return text