Add a tip on best pratices for Taipy/Template

[FlorianJacta]

Description Templates are not put in front of Taipy documentation even if they are extremely useful. It can answer a lot of concerns. See doc and issue.

Expected change Create a tip in the Knowledge base section on how to use template and why with other best practices.

You should make the changes of the documentation in this taipy-doc repo.

[jrobinAV]

I set a blocked label cause we need to re-discuss the template concept in Taipy.