Follow-up from "Better document how to enable Auto Monitoring"

The following discussions from !18949 (merged) should be addressed:

• @axil started a discussion: (+1 comment)

  @eread do you have a change reviewing this? Marcel already did a pass. I may have to resolve any comments in a following MR though, due to deadline constraints!

• @eread started a discussion: (+1 comment)

  @DylanGriffith @tkuah Is NGINX Ingress a hard requirement, or can other load balancers work? At the moment, it feels like a suggestion: https://docs.gitlab.com/ee/topics/autodevops/#requirements, but do we require specifically NGINX Ingress?

• @eread started a discussion:

  @DylanGriffith @tkuah we're adding Auto Monitoring to the list. Look ok?

  We have implied yes in the past: https://docs.gitlab.com/ee/topics/autodevops/#auto-monitoring.

• @eread started a discussion:

     1. **Ingress**, for response metrics.

  Or was our previous comment about response metrics just that we needed a certain version CC @tkuah @DylanGriffith?

• @eread started a discussion:

  Does that specifically work with this, @tkuah @DylanGriffith?

• @eread started a discussion:

  Just to check @tkuah @DylanGriffith, this is definitely Ingress only: http://docs-preview-ee-18949.178.62.207.141.xip.io/ee/user/clusters/applications.html#pointing-your-dns-at-the-external-endpoint.

  We used to have it in a more generic section: https://docs.gitlab.com/ee/user/project/clusters/#pointing-your-dns-at-the-external-endpoint.

• @eread started a discussion:

  That might be out of date, group level seems possible: http://docs-preview-ee-18949.178.62.207.141.xip.io/ee/user/clusters/applications.html#installing-applications.

  True @tkuah?