docs: add example for ingress

[rezachalak]

Description

The ingress definition in the helm chart is confusing, added example to help. There should not be host in the hosts section. Normally we define ingresses like:

ingress:
...
  hosts:
    -  step.example.com
...

But in this chart:

ingress:
...
  hosts:
    - host:  step.example.com
...

[CLAassistant]

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