make find_sccp_line_settings more joiny
specify all required columns in the query for sccp line settings
move SCCP line setting unittest to a separate class
add the find_pickup_members function in asterisk_conf_dao

Refactored some of the sip pickup tests to be able to reuse some code
refactor find_sip_pickup_settings to use find_pickup_members
Move pickup tests from sccp line tests to asterisk conf tests
add callgroup and pickup group to sccp_line_settings
remove unused import
reverse the meaning of member and pickup in pickupgroup interpretation

member maps to pickupgroup
pickup maps to callgroup
avoid an empty in_ filter
Merge branch '4711-pickupgroup-rebased'