[Feature request] Ability to generate a document without storing it.

[alpha14]

First thank you for making docuseal !

As I was testing the demo instance, I wondered if there could be a template option to avoid saving the documents on the server or notifying someone.
In that way, docuseal could act as templating service on public instances and preserve the privacy of the users.

For the context, there is a lot of paper documentation to fill in my country, and the official documents are not really "PDF friendly".

I believe it's similar to the once-off feature suggested in #94