Code review comment for ~hemanth-n/postgresql-charm:lp1956266

Could we split this into a few different merge proposals, since there's the addition of data_sync_retry to pg_settings_10.json, some description changes/typo fixes, and extension_destdir addition in pg_settings_11.json which I think should be handled in a separate commit as they're unrelated to the dot configuration parameters and addition of pgaudit settings.