Add missing backup_borg_base_path override

group_vars/matrix_servers

@@ -1882,6 +1882,8 @@ backup_borg_enabled: false
 
 backup_borg_identifier: matrix-backup-borg
 
+backup_borg_base_path: "{{ matrix_base_data_path }}/backup-borg"
+
 backup_borg_username: "{{ matrix_user_username }}"
 backup_borg_uid: "{{ matrix_user_uid }}"
 backup_borg_gid: "{{ matrix_user_gid }}"