Support multiple Services from GitLab Pages

What does this MR do?

Support multiple Services from GitLab Pages

GitLab Pages has multiple Service object definitions from the associated Helm Chart in https://gitlab.com/gitlab-org/charts/gitlab/-/tree/master/charts/gitlab/charts/gitlab-pages/templates.

Previously, we were only collecting one Service matching the Pages component app label, but there are multiple. This led to issues such as #1407 (closed).

Changelog: fixed

Test plan

1. Install Operator using the image tag from this MR (support-multiple-pages-services).
2. Apply a CR that sets global.pages.enabled=true.
3. Confirm that all Pages-related Services are reconciled.
4. Confirm that all Pages-related Services are not deleted.

$ kubectl get svc -l app=gitlab-pages
NAME                          TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)    AGE
gitlab-gitlab-pages           ClusterIP   10.12.7.6    <none>        8090/TCP   116s
gitlab-gitlab-pages-metrics   ClusterIP   10.12.4.91   <none>        9235/TCP   116s

Checklist

See Definition of done.

For anything in this list which will not be completed, please provide a reason in the MR discussion.

Required

• Merge Request Title and Description are up to date, accurate, and descriptive
• MR targeting the appropriate branch
• MR has a green pipeline on GitLab.com
• When ready for review, MR is labeled "~workflow::ready for review" per the Distribution MR workflow

Expected (please provide an explanation if not completing)

• Test plan indicating conditions for success has been posted and passes
• Documentation created/updated
• Tests added
• Integration tests added to GitLab QA
• Equivalent MR/issue for omnibus-gitlab opened
• Validate potential values for new configuration settings. Formats such as integer 10, duration 10s, URI scheme://user:passwd@host:port may require quotation or other special handling when rendered in a template and written to a configuration file.

Related issues

Related to #1407 (closed)