Deletion of TCT is blocked when specification refers not exist nodes

[mahjonp]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

1. apply trr.yaml:

apiVersion: naglfar.pingcap.com/v1
kind: TestResourceRequest
metadata:
  name: tidb-cluster
  namespace: mahjonp
spec:
  machines:
    - name: m1
  items:
    - name: control
      spec:
        memory: 8GB
        cores: 4
        machine: m1

2. apply tct.yaml

apiVersion: naglfar.pingcap.com/v1
kind: TestClusterTopology
metadata:
  name: tidb-cluster
  namespace: mahjonp
spec:
  resourceRequest: tidb-cluster
  tidbCluster:
    serverConfigs:
      tidb: |-
#        log.slow-threshold: 0
#      tikv: |-
#        readpool.storage.use-unified-pool: false
#        readpool.coprocessor.use-unified-pool: true
#      pd: |-
#        schedule.leader-schedule-limit: 4
#        schedule.region-schedule-limit: 2048
#        schedule.replica-schedule-limit: 64
    version:
      version: v4.0.8
#      tikvDownloadURL: http://fileserver.pingcap.net/download/builds/pingcap/tikv/164eb3d2dc94064f80b3ad3f6ae21cb071aaf36d/centos7/tikv-server.tar.gz
#      tidbDownloadURL: http://fileserver.pingcap.net/download/builds/pingcap/tidb/22feeb4aef750724f9f1321267a6bd5a661eb5e7/centos7/tidb-server.tar.gz
    control: n1
    tikv:
      - host: n1
        port: 20160
        statusPort: 20180
        deployDir: /disk1/deploy/tikv-20160
        dataDir: /disk1/data/tikv-20160
        logDir: /disk1/deploy/tikv-20160/log
#      - host: tikv-2
#        port: 20160
#        statusPort: 20180
#        deployDir: /disk1/deploy/tikv-20160
#        dataDir: /disk1/data/tikv-20160
#        logDir: /disk1/deploy/tikv-20160/log
#      - host: tikv-3
#        port: 20160
#        statusPort: 20180
#        deployDir: /disk1/deploy/tikv-20160
#        dataDir: /disk1/data/tikv-20160
#        logDir: /disk1/deploy/tikv-20160/log
    tidb:
      - host: n1
        deployDir: /disk1/deploy/tidb-4000
    pd:
      - host: n1
        deployDir: /disk1/deploy/pd-2379
        dataDir: /disk1/data/pd-2379
        logDir: /disk1/deploy/pd-2379/log
    monitor:
      - host: n1
        deployDir: /disk1/deploy/prometheus-8249
        dataDir: /disk1/deploy/prometheus-8249/data
    grafana:
      - host: n1
        deployDir: /disk1/deploy/grafana-3000

3. delete tct.yaml

2. What did you expect to see? (Required)

The tct is deleteded

3. What did you see instead (Required)

The deletion of tct is blocked because of below error:

2020-12-21T07:41:08.650Z	ERROR	controller-runtime.controller	Reconciler error	{"controller": "testclustertopology", "request": "mahjonp/tidb-cluster", "error": "control node not found: `n1`"}
github.com/go-logr/zapr.(*zapLogger).Error
	/go/pkg/mod/github.com/go-logr/zapr@v0.1.0/zapr.go:128
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).reconcileHandler
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.5.0/pkg/internal/controller/controller.go:258
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.5.0/pkg/internal/controller/controller.go:232
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).worker
	/go/pkg/mod/sigs.k8s.io/controller-runtime@v0.5.0/pkg/internal/controller/controller.go:211
k8s.io/apimachinery/pkg/util/wait.JitterUntil.func1
	/go/pkg/mod/k8s.io/apimachinery@v0.17.2/pkg/util/wait/wait.go:152
k8s.io/apimachinery/pkg/util/wait.JitterUntil
	/go/pkg/mod/k8s.io/apimachinery@v0.17.2/pkg/util/wait/wait.go:153
k8s.io/apimachinery/pkg/util/wait.Until
	/go/pkg/mod/k8s.io/apimachinery@v0.17.2/pkg/util/wait/wait.go:88

4. Affected version (Required)

5. Root Cause Analysis