Fixed syntax for "and" conditions (#2869)

[ti-srebot]

cherry-pick #2869 to release-1.1

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What problem does this PR solve?

Fixes a deployment error. (#2867)

<(.Values.monitor.create) and (.Values.monitor.grafana.create)>: can't give argument to non-function .Values.monitor.create

I have confirmed that both helm2 and helm3 work.

https://v2.helm.sh/docs/chart_template_guide/#operators-are-functions
https://helm.sh/docs/chart_template_guide/function_list/#and

What is changed and how does it work?

Fixed syntax.

Check List

Tests

• Manual test (add detailed scripts or steps below)

I used a v1.16 series k8s cluster.
The following command is used to check the operation.

kubectl create ns tidb-admin
helm repo add pingcap https://charts.pingcap.org/
kubectl apply -f https://raw.githubusercontent.com/pingcap/tidb-operator/master/manifests/crd.yaml
helm upgrade tidb-operator pingcap/tidb-operator -i --wait -n tidb-admin
helm upgrade tidb-cluster pingcap/tidb-cluster -i --wait -n tidb-admin \
  --set schedulerName=tidb-scheduler,pd.storageClassName=hostpath,tikv.storageClassName=hostpath,pd.replicas=1,tikv.replicas=1,tidb.replicas=1,monitor.create=true,monitor.grafana.create=true

Code changes

• Has Helm chart code change

Related changes

None.

Does this PR introduce a user-facing change?:

No.

[DanielZhangQD]

LGTM

[DanielZhangQD]

/merge

[ti-srebot]

/run-all-tests