[Bug] Unreliable missing teachers method

[ivanhrabcak]

Describe the bug
The get_missing_teachers method does not work in all schools (as the text is customizeable and our code relies on parsing HTML).

Error message

\edupage_api/__init__.py", line 191, in get_missing_teachers
    return Substitution(self).get_missing_teachers(date)
  File "C:\Users\xxx\AppData\Local\Programs\Python\Python311\Lib\site-packages\edupage_api\module.py", line 94, in impl
    return method(self, *method_args, **method_kwargs)
  File "C:\Users\xxx\AppData\Local\Programs\Python\Python311\Lib\site-packages\edupage_api\substitution.py", line 67, in get_missing_teachers
    _title, missing_teachers = missing_teachers_string.split(": ")
ValueError: not enough values to unpack (expected 2, got 1)

Version

• Edupage API version: 0.10.2
• Python version: 3.11

[ivanhrabcak]

Because of much the administrator can customize this feature, this cannot be easily fixed.

I've added a wontfix label.