Got errors when install ks-devops as a chart which the namespace is not kubesphere-devops-system

```
[root@node1 ~]# helm repo add ks https://kubesphere-sigs.github.io/ks-devops-helm-chart/
"ks" has been added to your repositories
[root@node1 ~]# helm repo list
NAME URL
ks https://kubesphere-sigs.github.io/ks-devops-helm-chart/
```

I try to install ks-devops via: `helm install test ks/ks-devops -n default`

But, got the following errors:
```
[root@node1 ~]# ks logs test-controller-68ffb86b59-469vg -c init-config
W0906 13:09:28.102923 1 client_config.go:552] Neither --kubeconfig nor --master was specified. Using the inClusterConfig. This might not work.
Error: cannot find ConfigMap kubesphere-devops-system/devops-config, error: configmaps "devops-config" not found
Usage:
jwt [flags]

Flags:
-h, --help help for jwt
--name string The name of target ConfigMap (default "devops-config")
--namespace string The namespace of target ConfigMap (default "kubesphere-devops-system")
-o, --output string The destination of the JWT output. Print to the stdout if it's empty.
-s, --secret string The secret for generating jwt

2021/09/06 13:09:28 cannot find ConfigMap kubesphere-devops-system/devops-config, error: configmaps "devops-config" not found
```

/kind bug

Reproduce the installation with `helm install test ks/ks-devops -n default` and inspect the `init-config` container logs. Trace how the chart and the `jwt` command locate the `devops-config` ConfigMap, especially the hard-coded `kubesphere-devops-system` namespace. Done means the chart can install in a different namespace without the reported missing-ConfigMap error.

Written by the indexing model from the issue text.