[repository] drop usage of no more necessary eschema_eid function
since the previous cset, we are guaranteed that repository's entity schema will
have their eid attribute properly set, so we don't have anymore to check
everytime if some entity schema's .eid attributes is set or not (and retrieve it
if not).
Related to #10450092
Add some entities
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As manager, you can access to entity creation forms by using the `site management`_ page.
.. _`site management`: ../manage
As regular user, the index page or the action box may propose some links to create entities according to the context.