backup-borg: disable mariadb/mysql/mongodb by default

group_vars/matrix_servers

@@ -3271,6 +3271,9 @@ matrix_pantalaimon_homeserver_url: "{{ matrix_addons_homeserver_client_api_url }
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 backup_borg_enabled: false
+backup_borg_mariadb_enabled: false
+backup_borg_mysql_enabled: false
+backup_borg_mongodb_enabled: false
 
 backup_borg_identifier: matrix-backup-borg
 backup_borg_storage_archive_name_format: matrix-{now:%Y-%m-%d-%H%M%S}