Several changes were done because of the code review:
* The category of the module is now "Warehouse", in alignment
with the categories user in OCA (https://odoo-community.org/shop)
* The list of fields in the depends() for the method
_compute_last_inventory_date() missed several fields, that are
now listed as dependencies.
* A new unit test has been added to account for the concern of the
functional needing a compute_sudo in its definition, just in case
a non privileged stock user was stuck into permission problems.
This new module adds a stored computed field on locations that stores
the last inventory date for the location, for validated inventories.
This is only computed for leaf locations, not parent ones.