[entity,storage] remove hackish code from the bfss path The ClientConnection/Connection duality brought some painful hacks that are no longer needed. Hence we can send entity._cw_update_attr_cache and ._cw_dont_cache_attribute to the grave. Related to #3837233

[system]
db-driver   = sqlite
adapter     = native
db-name     = tmpdb-multi
db-encoding = UTF-8