### Motivation
if you deploy pulsar using the helm chart and disable monitoring with
```
extras:
dashboard: no
```
but you have the ingress of the dashboard set to true
```
dashboard:
ingress:
enabled: true
```
the helm chart will create an ingress that points to a non-existing service because the dashboard itself was not deployed.
### Modifications
I've added the same check that is already in place in dashboard-service and dashboard-deployment
### Verifying this change
I dont know of any automated tests, i tested it manually. In the end it's the same "if" that is already in place in dashboard-service and dashboard-deployment
### Does this pull request potentially affect one of the following parts:
Affects deployment via helm chart. An unwanted ingress object is suppressed.
### Documentation
no documentation need
This patch allows tls to be enabled with an empty secretName for ingress controllers might be able to provide a default certificate.
Fixes#5858, provides better defaults for the Ingress object and allows TLS to be enabled with an empty secretName.
### Motivation
The current helm chart can create an Ingress with TLS, but it requires a secretName to be added. This is not an Ingress requirement and, in some cases, the ingress controller can provide a default certificate when the Ingress object does not declare one.
### Modifications
Modifications include `values.yaml` and `dashboard-ingress.yaml` to address the issue.
Allows to opt-in for an ingress on top of the dashboard service.
This is very important in production-grade deployments where
you want to expose the Pulsar dashboard through an easy to remember URL.
