session is management issue

[Sashabus]

after market object is initialized inside of client, either via login_cookies or login method the session id(from _get_session_id()) value given to the constructor of market object is associated with a wrong domain, instead of:

self._session.cookies.get_dict()['sessionid']

it shoud be initialized with session id from:

self._session.cookies.get_dict(domain="steamcommunity.com", path="/").get('sessionid')

I am only working with buy order functionality of market so simply giving steamcommunity sessionid to market might lead to some unexpected issues in other methods, however for interaction with buy orders correct session id must be set.