Out of date PIT Tutorial 

PIT tables Tutorial page is currently out of date, suggesting we use `stage_tables` instead of the updated `stage_tables_ldts` as [we changed it to in 0.9.0](https://dbtvault.readthedocs.io/en/latest/migration_guides/)

![image](https://user-images.githubusercontent.com/25080503/219043041-5acccbdb-7e0d-4fd1-bc07-6c8ee2782a4e.png)

This needs to be updated
