Implement CI DeWeb deployement

[pivilartisant]

Design and create a reference Github Actions that allow automatically deploying deweb sites and keeping them updated at every push on main.

This work should reuse the existing CLI system as much as possible.

The goal is to slowly move all our websites to the deweb, avoid having to manually keep docs.massa up-to-date at the same version as docs.massa.net. Let's package this work in a nice way, document it, distribute it and announce it so that community developers and partners can seriously start using the deweb in a practical way.
It can come for example with a sample github repo that they can easily fork for their purpose.

[SlnPons]

Please add details in this issue and make sure to cover the comment here: #141 (comment)