no need to stop on lack of cookie / clean code

In `client.py`, the test
`
if 'PHPSESSID' not in req.cookies:
raise PyAtomeError("Login error: Please check your username/password: %s ", str(req.text))
`
is no more usefull.
It shall be suppressed, as it triggers some errors.

I've made a project https://github.com/jugla/pyKeyAtome to clean the code and reformat it.
I've also clean the dependancy.

If you want , I will be very pleased to commit in your space.

Thanks in advance for your feed back.

NB : it comes along the improment, I suggest in HomeAssistant.

Open client.py and locate the PHPSESSID check shown in the issue. Remove the obsolete error-triggering behavior and verify that requests without this cookie no longer produce the reported login error.

Written by the indexing model from the issue text.