CI to check and update documentation

[JuanSapriza]

I see the need for two new CIs:

1. One that updates the Documentation on every PR merge by running

cd docs
make clean
make html

Also... this commands are not working... So we need to fix that as well.
#529

2. One to check the type of documentation being uploaded/generated.
   I really liked the automatic generation of documentation, but the I also find it a bit hieroglyphic:
   

@JoseCalero @LuigiGiuffrida98 @Ho3eintaji @davideschiavone