Chore: remove unused import from recent push

Author: dbmalkovsky

modules/flowable-engine/src/main/java/org/flowable/engine/impl/history/DefaultHistoryManager.java

@@ -36,7 +36,6 @@
 import org.flowable.engine.impl.persistence.entity.HistoricDetailVariableInstanceUpdateEntity;
 import org.flowable.engine.impl.persistence.entity.HistoricProcessInstanceEntity;
 import org.flowable.engine.impl.persistence.entity.ProcessDefinitionEntity;
-import org.flowable.engine.impl.runtime.callback.ProcessInstanceState;
 import org.flowable.engine.impl.util.TaskHelper;
 import org.flowable.engine.runtime.ActivityInstance;
 import org.flowable.entitylink.api.history.HistoricEntityLinkService;