Remove namespaces from Operator Helm chart

[dnskr]

Description

The PR removes redundant namespace from Operator Helm chart templates. Similar to minio/minio#16968.
Note: There is no namespace properties in Tenant Helm chart templates.

Motivation and Context

Motivation - keep code smaller and cleaner.
Context - Helm creates Kubernetes resources (Deployment, ConfigMap, Service, Ingress etc.) in the same namespace where release installed, i.e. .Release.Namespace is used by default.

How to test this PR?

Install the chart to qwerty namespace:

$ helm install test helm/operator -n qwerty
NAME: test
LAST DEPLOYED: Sat Jun 17 00:09:16 2023
NAMESPACE: qwerty
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
   ...

Check reqources in the qwerty namespace:

$ kubectl get all -n qwerty
NAME                                  READY   STATUS    RESTARTS   AGE
pod/console-869647699-rm242           1/1     Running   0          37s
pod/minio-operator-6f47c94d76-46jpg   1/1     Running   0          37s
pod/minio-operator-6f47c94d76-dgtd2   1/1     Running   0          37s

NAME               TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)             AGE
service/console    ClusterIP   10.99.126.7     <none>        9090/TCP,9443/TCP   37s
service/operator   ClusterIP   10.100.122.50   <none>        4221/TCP            37s
service/sts        ClusterIP   10.98.185.5     <none>        4223/TCP            37s

NAME                             READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/console          1/1     1            1           37s
deployment.apps/minio-operator   2/2     2            2           37s

NAME                                        DESIRED   CURRENT   READY   AGE
replicaset.apps/console-869647699           1         1         1       37s
replicaset.apps/minio-operator-6f47c94d76   2         2         2       37s

[shtripat]

LGTM. Verified.