Update docker/build-push-action action to v6 (#1729)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[docker/build-push-action](https://redirect.github.com/docker/build-push-action)
| action | major | `v5` -> `v6` |

---

### Release Notes

<details>
<summary>docker/build-push-action (docker/build-push-action)</summary>

###
[`v6`](https://redirect.github.com/docker/build-push-action/compare/v5...v6)

[Compare
Source](https://redirect.github.com/docker/build-push-action/compare/v5...v6)

</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-publish.yml

@@ -58,7 +58,7 @@ jobs:
             type=sha,format=long
       - name: Build and push Docker image
         id: build-and-push
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           push: true
           context: ${{ matrix.context }}