[GSTG] Disable gitlab-zoekt.certificates.initContainers

What does this MR do?

This MR sets gitlab-zoekt.certificates.initContainers.enabled to false to address the issue in gitlab-com/gl-infra/delivery#21528 (closed) before re-introducing Add custom certificates support [Attempt 2] (gitlab-org/cloud-native/charts/gitlab-zoekt!131 - merged).

Author Check-list

Please read the Contributing document and once you do, complete the following:

• Check if all of the following apply:
  • Assign to the correct reviewer per the contributing document
  • Apply the correct metadata per the contributing document
  • Link to related MRs for applying the changes on other environments
  • Link to related Chef changes
  • If necessary link to a Criticality 4 Change Request issue

Reviewer Check-list

• Check if all of the following apply:
  • Reviewed the diff jobs to confirm changes are as expected
  • No changes shown in the diffs not associated with this MR - This may require a rebase or further investigation

Applier Check-list

• Make sure there is no ongoing deployment for the affected envs before merging (see #announcements slack channel)