'sssctl config-check' shows WARNING about 'config_file_version' option in sssd.conf on Red Hat Enterprise Linux system after 'realm join'

Issue

• During the domain join process on a server, the parameter config_file_version is automatically added to the sssd.conf file. However, this parameter is not documented in the official sssd.conf man page, and its presence leads to the following error when SSSD is run in debug mode:

[sssd] [sss_ini_call_validators] (0x0020): [rule/allowed_sssd_options]: Attribute 'config_file_version' is not allowed in section 'sssd'. Check for typos.