Alter or clear audited domains list on Pi-hole instance.

You can mark domains as audited to simply hide these, but there is no web interface to manage domains that have been already audited.
Alter database directly
Inspect table that stores audited domains.
dietpi@DietPi:~$ sqlite3 /etc/pihole/gravity.db ".schema domain_audit"
CREATE TABLE domain_audit ( id INTEGER PRIMARY KEY AUTOINCREMENT, domain TEXT UNIQUE NOT NULL, date_added INTEGER NOT NULL DEFAULT (cast(strftime('%s', 'now') as int)) );
Display audited domains.
dietpi@DietPi:~$ sqlite3 /etc/pihole/gravity.db "SELECT domain FROM domain_audit"
incoming.telemetry.mozilla.org trello.com
Delete specific domain.
dietpi@DietPi:~$ sudo sqlite3 /etc/pihole/gravity.db "DELETE FROM domain_audit where domain='trello.com'"
Delete all domains.
dietpi@DietPi:~$ sudo sqlite3 /etc/pihole/gravity.db "DELETE FROM domain_audit"
Alter database using pihole utility
Add an audited domain.
dietpi@DietPi:~$ pihole -a audit trello.com
Clear audited domains list.
dietpi@DietPi:~$ pihole -a clearaudit