Missing stack traces in logs

[raphj]

To ease debugging, please convert some warnings to errors with stack traces in TaskMacroUpdateEventListener, for instance:

                logger.warn("Failed to retrieve the document that contains the Task Object with id [{}]: [{}].",
                    taskReference, ExceptionUtils.getRootCauseMessage(e));

to:

                logger.error("Failed to retrieve the document that contains the Task Object with id [{}]",
                    taskReference, e);