Remove platform and ComposedTaskJobExecutionStatus getters/setters

These are not used by the thinTaskExecutions and can be removed
Also removed platformName because it is not used at all.  Unlike ComposedTaskJobExecutionStatusi
 that is used for setting the status and initialized through the constructor.

This was to be a part of PR spring-cloud#5813 but was missed by the committer.

spring-cloud-dataflow-rest-resource/src/main/java/org/springframework/cloud/dataflow/rest/resource/TaskExecutionThinResource.java

@@ -79,7 +79,6 @@ public class TaskExecutionThinResource extends RepresentationModel<TaskExecution
 
 	private String schemaTarget;
 
-	private String platformName;
 
 	public TaskExecutionThinResource() {
 	}
@@ -88,7 +87,6 @@ public TaskExecutionThinResource(AggregateTaskExecution aggregateTaskExecution)
 		this.executionId = aggregateTaskExecution.getExecutionId();
 		this.schemaTarget = aggregateTaskExecution.getSchemaTarget();
 		this.taskName = aggregateTaskExecution.getTaskName();
-		this.platformName = aggregateTaskExecution.getPlatformName();
 		this.externalExecutionId = aggregateTaskExecution.getExternalExecutionId();
 		this.parentExecutionId =aggregateTaskExecution.getParentExecutionId();
 		this.startTime = aggregateTaskExecution.getStartTime();
@@ -179,25 +177,10 @@ public void setSchemaTarget(String schemaTarget) {
 		this.schemaTarget = schemaTarget;
 	}
 
-	public String getPlatformName() {
-		return platformName;
-	}
-
-	public void setPlatformName(String platformName) {
-		this.platformName = platformName;
-	}
 	public void setTaskExecutionStatus(String taskExecutionStatus) {
 		this.taskExecutionStatus = taskExecutionStatus;
 	}
 
-	public String getComposedTaskJobExecutionStatus() {
-		return composedTaskJobExecutionStatus;
-	}
-
-	public void setComposedTaskJobExecutionStatus(String composedTaskJobExecutionStatus) {
-		this.composedTaskJobExecutionStatus = composedTaskJobExecutionStatus;
-	}
-
 	/**
 	 * Returns the calculated status of this {@link TaskExecution}.
 	 *