Update docker/build-push-action digest to ee4ca42 (#152)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[docker/build-push-action](https://redirect.github.com/docker/build-push-action)
([changelog](https://redirect.github.com/docker/build-push-action/compare/263435318d21b8e681c14492fe198d362a7d2c83..ee4ca427a2f43b6a16632044ca514c076267da23))
| action | digest | `2634353` → `ee4ca42` |

---

### Configuration

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Automerge - At any time (no schedule defined).

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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/ci.yml

@@ -84,7 +84,7 @@ jobs:
             type=sha,format=long,prefix=sha-
             type=raw,value=latest,enable={{is_default_branch}}
 
-      - uses: docker/build-push-action@263435318d21b8e681c14492fe198d362a7d2c83 # v6
+      - uses: docker/build-push-action@ee4ca427a2f43b6a16632044ca514c076267da23 # v6
         with:
           file: ${{ matrix.dockerfile }}
           tags: ${{ steps.meta.outputs.tags }}