CI vcluster: Wait for cert-manager

What does this MR do?

CI vcluster: Wait for cert-manager

Wait for rollout of all cert-manager Deployments before proceeding with the Operator installation.

The Operator needs a webhook Certifcate, which can not be created if the ceret-manager webhook is not up.

Relates #1679 (closed)

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
  • Confirm review_vcluster128 passes without retry. https://gitlab.com/gitlab-org/cloud-native/gitlab-operator/-/jobs/7044994161
• 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

Closes #1679 (closed)