Update registry1.dso.mil/ironbank/opensource/grafana/promtail Docker tag to v3.4.2

This MR contains the following updates:

Package	Update	Change
registry1.dso.mil/ironbank/opensource/grafana/promtail (source)	minor	v3.3.2 -> v3.4.2
registry1.dso.mil/ironbank/opensource/grafana/promtail (source)	minor	3.3.2 -> 3.4.2

Complete MR checklist

Assignee

• Followed upgrade instructions outlined in docs/DEVELOPMENT_MAINTENANCE.md
• Update Docs with new/updated steps as needed
• Tested and Validated Changes made with supporting info like logs or screenshots from test pipelines

Add supporting info below

Reviewer only

• Tested and Validated changes

---

Configuration

Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

Automerge: Disabled by config. Please merge this manually once you are satisfied.

Rebasing: Whenever MR becomes conflicted, or you tick the rebase/retry checkbox.

Ignore: Close this MR and you won't be reminded about these updates again.

---

• If you want to rebase/retry this MR, check this box

---

This MR was automatically generated by Renovate Bot.

Upgrade Notices

N/A