chore(engine): remove suspended/failed from historic case instance

- removes the methods isFailed()/isSuspended() from the interface
  HistoricCaseInstance
- removes the methods for querying these states from the query interface
- adapts the REST API accordingly

related to CAM-2840
chore(engine-rest): remove POST for historic case activity instances

- the POST query does not offer more functionality than the GET query
  so it is not required

related to CAM-2842