feat: update docker.io/ianw/quickchart docker tag to v1.8.1

[sebastien-prudhomme]

This PR contains the following updates:

Package	Update	Change
docker.io/ianw/quickchart	minor	v1.7.1 -> v1.8.1

---

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 PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

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

---

This PR has been generated by Renovate Bot.

[sebastien-prudhomme]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
• you rename this PR's title to start with "rebase!" to trigger it manually

The artifact failure details are included below:

File name: undefined

Post-upgrade command 'bash .github/bump-chart-version.sh '{{{parentDir}}}' '{{{isMajor}}}' '{{{isMinor}}}' '{{{isPatch}}}'' has not been added to the allowed list in allowedPostUpgradeCommands