Documentation update to support Operator 3.0 changes

[synhershko]

No description provided.

[github-actions]

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[synhershko]

@prudhvigodithi @gaiksaya fyi

[prudhvigodithi]

Thanks @synhershko will take a look.

[josedev-union]

Suggested change

	Then run `kubectl apply -f cluster.yaml`:
	Then apply it:

[josedev-union]

Suggested change

If you watch the cluster (for example, `watch -n 2 kubectl get pods`), you will see that after a few seconds the Operator will create several pods. First, a bootstrap pod will be created (`my-first-cluster-bootstrap-0`) that helps with initial master discovery. Then three pods for the OpenSearch cluster will be created (`my-first-cluster-nodes-0/1/2`), and one pod for the dashboards instance. After the pods are appearing as ready, which normally takes about 1-2 minutes, you can connect to your cluster using port-forwarding.

If you watch the cluster (for example, `watch -n 2 kubectl get pods`), you will see that after a few seconds the Operator will create several pods. First, a bootstrap pod will be created (`my-first-cluster-bootstrap-0`) that helps with initial master discovery. Then three pods for the OpenSearch cluster will be created (`my-first-cluster-masters-0/1/2`), and one pod for the dashboards instance. After the pods are appearing as ready, which normally takes about 1-2 minutes, you can connect to your cluster using port-forwarding.

[josedev-union]

Suggested change

	Run `kubectl port-forward svc/my-first-cluster-dashboards 5601`, then open [http://localhost:5601](http://localhost:5601) in your browser and log in with the default demo credentials `admin / admin`.
	Run `kubectl port-forward svc/my-first-cluster-dashboards 5601`, then open [http://localhost:5601](http://localhost:5601) in your browser and log in using dashboard user or admin user credential. You can get them from `my-first-cluster-admin-password` and `my-first-cluster-dashboards-password` secrets.

[josedev-union]

Suggested change

	Then open a second terminal and run:
	```bash
	curl -k -u admin:admin https://localhost:9200/_cat/nodes?v
	```
	Then open a second terminal and run the following command. You can get the admin credential from `my-first-cluster-admin-password` secrets.
	```bash
	curl -k -u admin:admin_password https://localhost:9200/_cat/nodes?v

[kolchfa-aws]

@synhershko Could you also fix DCO?

[kolchfa-aws]

@synhershko Please let me know when you're finished addressing technical comments, and we'll move the PR to doc review and then editorial review. Thanks!