chore: cleanup duplicated code

[googs1025]

/kind cleanup

• NodeLister has been initialized in newDescheduler, delete the duplicate code

• Delete unused ctx

  func newDescheduler(rs *options.DeschedulerServer, deschedulerPolicy *api.DeschedulerPolicy, evictionPolicyGroupVersion string, eventRecorder events.EventRecorder, sharedInformerFactory informers.SharedInformerFactory) (*descheduler, error) {
  podInformer := sharedInformerFactory.Core().V1().Pods().Informer()
  podLister := sharedInformerFactory.Core().V1().Pods().Lister()
  nodeLister := sharedInformerFactory.Core().V1().Nodes().Lister()
  namespaceLister := sharedInformerFactory.Core().V1().Namespaces().Lister()
  priorityClassLister := sharedInformerFactory.Scheduling().V1().PriorityClasses().Lister()
  
  getPodsAssignedToNode, err := podutil.BuildGetPodsAssignedToNodeFunc(podInformer)
  if err != nil {
      return nil, fmt.Errorf("build get pods assigned to node function error: %v", err)
  }
  
  return &descheduler{
      rs:                         rs,
      podLister:                  podLister,
      nodeLister:                 nodeLister,
      namespaceLister:            namespaceLister,
      priorityClassLister:        priorityClassLister,
      getPodsAssignedToNode:      getPodsAssignedToNode,
      sharedInformerFactory:      sharedInformerFactory,
      evictionPolicyGroupVersion: evictionPolicyGroupVersion,
      deschedulerPolicy:          deschedulerPolicy,
      eventRecorder:              eventRecorder,
  }, nil
  }

[a7i]

/lgtm

[googs1025]

/assign @damemi /PTAL thanks!

[ingvagabund]

/approve

[k8s-ci-robot]

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