chore(deps): update docker/build-push-action action to v6 (#23)

This PR contains the following updates:

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

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### Release Notes

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

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

[Compare Source](https://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

---

This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
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Reviewed-on: #23
Co-authored-by: Renovate Bot <renovate@dzeio.com>
Co-committed-by: Renovate Bot <renovate@dzeio.com>

.github/workflows/build_docker.yml

@@ -55,7 +55,7 @@ jobs:
       uses: docker/setup-buildx-action@v3
 
     - name: Build and push the project
-      uses: docker/build-push-action@v5
+      uses: docker/build-push-action@v6
       with:
         context: .
         push: true