[security] check attributes: dispatch on the "add" action if entity was just created cw_set on a just-created entity (i.e. created in the same transaction) should behave the same as setting the attribute directly on creation: check the 'add' permissions, not 'update'. Closes #4740310.

missing-dep-for-interpreter make => make | build-essential | dpkg-dev (usr/share/pyshared/cubicweb/skeleton/debian/rules.tmpl)