quickfix mensa json parsing

mensa.py

@@ -119,6 +119,7 @@ def mensa(update: Update, context: CallbackContext):
     else:
         message = "Das Essen für %s in der %s \n\n" % (today_data["date"], MENSA_NAME[which])
         for cat in today_data['categories']:
+            try:
                 label = cat['name']
                 meals = cat['meals']
                 if label not in filter_categories and (
@@ -129,6 +130,8 @@ def mensa(update: Update, context: CallbackContext):
                     for meal in meals:
                         meal_line += meal['name'].strip() + "\n"
                     message += meal_line + '\n'
+            except:  # TODO: catch correct exception
+                print("Could not fetch meal. Skipping.")
 
     update.message.reply_text(message, ParseMode.MARKDOWN)