ECMS-6296: Update ECMS unit tests to adapt change from JCR-2307
ECMS-5998: Can't import intranet folder after deleting node "exo:actions"

Fix description:
- Update the node type definition of exo:actionable. Property exo:actions is not mandatory any more.
- Add new upgrade plugin ActionableNodeTypeUpgradePlugin to update legacy data.
Merge commit '4bd9e286850e94a14ca530ffd0065108e91c6127' into HEAD