CLOUDP-290847: Remove cert hash annotations

[m1kola]

Summary

This refactors the way we do cert rotation: we no longer write certificate hashes into annotations of STS. This simplifies the flow and will make it easier to implement agent cert rotation (CLOUDP-290847) in a similar way.

Proof of Work

Existing tests must be green.

Checklist

• Have you linked a jira ticket and/or is the ticket in the title?
• Have you checked whether your jira ticket required DOCSP changes?
• Have you added changelog file?
  • use skip-changelog label if not needed
  • refer to Changelog files and Release Notes section in CONTRIBUTING.md for more details

[MaciejKaras]

I see that tlsCertHash and tlsCertPath are calculated here and also in the other controllers/operator/mongodbreplicaset_controller.go. Can we move this logic to common controller?
I thought about method like:

func (r *ReconcileCommonController) tlsCertHashAndPath(ctx, ...) (string, string) {
  tlsCertHash := enterprisepem.ReadHashFromSecret(ctx, r.SecretClient, mrs.Namespace, certSecretName, "", log)
  if tlsCertHash == "" {
    return "", ""
  }
  
  return tlsCertHash, fmt.Sprintf("%s/%s", util.TLSCertMountPath, tlsCertHash)  
}

[m1kola]

I would like to leave this out of the scope of this PR. Here I want to make a minimal change so that I can progress with my main goal (agent cert rotation).

There are more places where we read the secret and calculate the hash and I have a feeling that after adding agent cert rotation it will be a bit more clear if there is a pattern which we can abstract somehow. I'll look into this if I have time left after implementing agent cert rotation.

[MaciejKaras]

Understand. In that case can you add TODO item for improving this later?

[m1kola]

I've added a to do in another branch (I'll eventually push the to do or a change to #389). Don't want to push to this branch and wait for CI again.

[m1kola]

e2e_om_ops_manager_queryable_backup is red, but it is a known CI issue and is not related to this change. Merging.