[skeleton] Use unittest.main directly Instead of lgc.testlib.unittest_main as they are identical.

[devtools/testlib] Disable pause trace in setUp Closes #9856028.

[test] Remove dependency on person cube in devtools package

[pkg] add missing python-tz dependency

[edit controller] Fix composite entity reparenting when inlined This implies handling the reparenting case sooner, otherwise the child entity modifications are cancelled (see 113e9da47afc). Add a new test to ensure non-regression in all previous tests. Closes #10291977.

[forms] Do not raise errors on composite required relation being deleted The entity included in the composite will be deleted in such a case, so the field is not required even when the cardinality is '1' or '+'. Related to #8529868

[edit controller] Cancel RQL queries to be performed on entities to be deleted Composite relation removal via the EditController trigger an entity removal. Changes on such a to-be-removed entity must be cancelled as they may trigger integrity errors before the deletion occurs. Closes #8529868.

[edit controller] fix handling of removal of subentities from an edit form In CubicWeb 3.18 the semantics of dropping a composite relation were changed. It had before the effect of deleting the subentities. Now the edit controller must handle this by itself (it was not adapted then by mistake). So if it detects the removal of a composite relation (on the browser side, the user clicked on the "remove" action), the subentity is now explicitly deleted. It was chosen not to change the form generation but the EditController: - to ensure pre-3.18 forms backward compat - to avoid the introduction of a specific entity-deletion API (RQL is probably our best API for complex DB operations) Related to #8529868.

remove unused import

[editcontroller] a slight code reorganisation, in preparation for a fix * `entity` defined at method entry * a combined `continue` and a dedent of the next big block * some vertical white space Related to #8529868.