BZ-1069117 - Modal with NPE shown after comleting a Human Task in task list

(cherry picked from commit 75bc7e810f9fa508d67087b0a9b6179768e4a34b)
BZ-1070739 - Remote REST rarely throws IllegalStateException: EntityManager is closed when load tested by multiple threads using PPI and HumanTask process

(cherry picked from commit b3ff7f248138b5c5c37870d09740d1fcba0c8451)