cubicweb #4891547 [dataimport] NoHookRQLObjectStore broken by new connection handling [validation pending]

still attempt access to '.session' which raise an exception:

 File "/home/syt/src/clients/SAEM/cubicweb/dataimport.py", line 620, in session
   return self._cnx.repo._get_session(self._cnx.sessionid)
 File "/home/syt/src/clients/SAEM/cubicweb/server/repository.py", line 937, in _get_session
   raise BadConnectionId('No such session %s' % sessionid)
BadConnectionId: No such session internal
prioritynormal
typebug
done in3.20.4
load1.000
load left0.000
closed by#0b141ffcdd74 [dataimport] massive renaming of session to cnx
patch[dataimport] massive renaming of session to cnx [applied]