Re-integrated EU eIDAS-compliant Italian SPID Authentication

**Describe the solution you'd like** Italian Government adopted DECIDIM to develop it's national partecipation platform partecipa.gov.it .

Italia Government modified Decidim introducing EU eIDAS-compliant SPID Autentication, along with other features available here https://github.com/dipartimentofunzionepubblica/partecipa .

**Additional context** This ticket is to officially re-integrate all the Decidim modification that enable operations of partecipa.gov.it platform without any customization.

Considering the new Decidiamo! Italian Community of Decidim https://decidiamo.it it's valuable to consider in the roadmap proper community management to integrate all the upcoming modification done during the development of Open Rousseau https://openrousseau.org .

**Funded by** We could have some match funding by Decidiamo! community member