chore(deps): update docker/setup-buildx-action action to v3.12.0 (#1438)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[docker/setup-buildx-action](https://redirect.github.com/docker/setup-buildx-action)
| action | minor | `v3.11.1` -> `v3.12.0` |

---

### Release Notes

<details>
<summary>docker/setup-buildx-action
(docker/setup-buildx-action)</summary>

###
[`v3.12.0`](https://redirect.github.com/docker/setup-buildx-action/compare/v3.11.1...v3.12.0)

[Compare
Source](https://redirect.github.com/docker/setup-buildx-action/compare/v3.11.1...v3.12.0)

</details>

---

### 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.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

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.github/workflows/docker-test.yml

@@ -135,7 +135,7 @@ jobs:
           persist-credentials: false
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@e468171a9de216ec08956ac3ada2f0791b6bd435 # v3.11.1
+        uses: docker/setup-buildx-action@8d2750c68a42422c14e847fe6c8ac0403b4cbd6f # v3.12.0
 
       - name: Build server image
         run: |