Replace and fix "Update specific lines in sssd.conf" task

Use of the "Update specific lines in sssd.conf" task is clunky and actually broken.

As it is currently written, it does not really know which section of the sssd.conf file the common_sssd_extra_configs VAR key value pairs should be set in. If it doesn't find a matching key, it will just append it to the end of the file, which likely is not what we want.