AD joins fail with error "kerberos_kinit_password example.com\user@EXAMPLE.COM failed: Client not found in Kerberos database"

Issue

• Cannot join AD domain with 'realm join'.
• The command (realm join example.com -U 'example.com\user') fails.
• 'realm join' fails with "kerberos_kinit_password example.com\user@EXAMPLE.COM failed: Client not found in Kerberos database"