Backport GITLAB_ZOEKT_VERSION to 1.11.2

What does this MR do and why?

Bumps GITLAB_ZOEKT_VERSION from 1.11.1 to 1.11.2 on 18-10-stable-ee.

`v1.11.2` is a backport of refactor: bump schemaVersion to initiate force reindexing which fixes a bug where the Zoekt indexer incorrectly performs an incremental index after a force push, resulting in stale or missing search results for self-managed customers on GitLab 18.10.

• Original issue: #593947 (closed)

Backport chain for 18.10 (SM)

1. ✅ `gitlab-zoekt-indexer` — cherry-picked fix onto `v1.11.1`, tagged `v1.11.2`
2. ⏳ `gitlab-org/build/CNG` — MR, builds `cng/gitlab-zoekt:v1.11.2` on `18-10-stable`
3. ⭐ `gitlab-org/gitlab` — this MR on `18-10-stable-ee` bumping `GITLAB_ZOEKT_VERSION` to `1.11.2`
4. ⏳ `cloud-native/charts/gitlab-zoekt` — MR on `main` bumping chart to `3.8.5` with image `v1.11.2`
5. ⏳ `gitlab-org/charts/gitlab` — MR on `9-10-stable` bumping `gitlab-zoekt` to `3.8.5`

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• This MR is backporting a bug fix, documentation update, or spec fix, previously merged in the default branch.
• The MR that fixed the bug on the default branch has been deployed to GitLab.com (not applicable for documentation or spec changes).
• The MR title is descriptive (e.g. "Backport of 'title of default branch MR'"). This is important, since the title will be copied to the patch blog post.
• Required labels have been applied to this merge request
  • severity label and bug subtype labels (if applicable)
  • If this MR fixes a bug that affects customers, the customer label has been applied.
• This MR has been approved by a maintainer (only one approval is required).
• Ensure the e2e:test-on-omnibus-ee job has succeeded, or if it has failed, investigate the failures. If you determine the failures are unrelated, you may proceed. If you need assistance investigating, reach out to a Software Engineer in Test in #s_developer_experience.

Note to the merge request author and maintainer

If you have questions about the patch release process, please:

• Refer to the patch release runbook for engineers and maintainers for guidance.
• Ask questions on the #releases Slack channel (internal only).
• Once the backport has been merged, the commit changes will be automatically deployed to a release environment that can be used for manual validation. See after merging runbook for details.