Gestion unifiée des auteurs et autrices (#2352)

* Use is_author again

* Symmetry

* meilleure migration

* Clean

* climate

* fix

* Update app/views/admin/communication/authors/index.html.erb

* Update app/views/admin/communication/authors/show.html.erb

Co-authored-by: Sébastien Gaya <sebastien.gaya@gmail.com>

* Update app/views/admin/communication/authors/show.html.erb

Co-authored-by: Sébastien Gaya <sebastien.gaya@gmail.com>

* update_author_status_if_necessary

* author

* find_cohorts

* fix

* fix

* fix

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Co-authored-by: Sébastien Gaya <sebastien.gaya@gmail.com>