Deep clone dashboards, including upstream models

[paoliniluis]

Is your feature request related to a problem? Please describe.
When you clone dashboards based on models the source models are not cloned as well, which might be an interesting use case when a user wants to take the entire lineage of objects to make it's own version of the dashboard (from the data to the viz)

Describe the solution you'd like
An option on dashboard cloning to make a deep deep copy (that includes the models as well)

Describe alternatives you've considered
Via serialization

How important is this feature to you?
Requested by a customer that has a lot of tenants and each tenant has a default data model that they might want to extend

Additional context
This should be defaulted to false