Investigate handling updates prior to login

[Lonami]

Apparently some updates like updateLoginToken happen before login (original report) but currently fails because we don't have entities (original report):

[ERROR/2020-05-13 08:30:11,237] asyncio: Task exception was never retrieved
future: <Task finished name='Task-10' coro=<UpdateMethods._dispatch_update() done, defined at /home/kp/unlogged/venv/lib/python3.8/site-packages/telethon/client/updates.py:382> exception=AttributeError("'NoneType' object has no attribute 'user_id'")>
Traceback (most recent call last):
  File "/home/kp/unlogged/venv/lib/python3.8/site-packages/telethon/client/updates.py", line 563, in getitem
    return self.dict[builder]
KeyError: <class 'telethon.events.raw.Raw'>

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/kp/unlogged/venv/lib/python3.8/site-packages/telethon/client/updates.py", line 420, in _dispatch_update
    event = built[type(builder)]
  File "/home/kp/unlogged/venv/lib/python3.8/site-packages/telethon/client/updates.py", line 566, in getitem
    self.update, self.others, self.client._self_input_peer.user_id)
AttributeError: 'NoneType' object has no attribute 'user_id'