WikiException is silently ignored

https://sentry.fsmpi.rwth-aachen.de/protokollsystem/protokollsystem/issues/6/

WikiException: HTTP status code 500 on action login.
(1 additional frame(s) were not displayed)
...
  File "celery/app/trace.py", line 629, in __protected_call__
    return self.run(*args, **kwargs)
  File "program/tasks.py", line 585, in push_to_wiki_async
    with WikiClient() as wiki_client, app.app_context():
  File "program/wiki.py", line 42, in __enter__
    self.login()
  File "program/wiki.py", line 56, in login
    token_answer = self.do_action("login", method="post", lgname=self.user)
  File "program/wiki.py", line 118, in do_action
    req.status_code, action))

WikiException: HTTP status code 500 on action login.