chore(deps): update docker/build-push-action action to v6 (#2)

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This PR contains the following updates:

| Package | Type | Update | Change | OpenSSF |
|---|---|---|---|---|
|
[docker/build-push-action](https://togithub.com/docker/build-push-action)
| action | major | `v5` -> `v6` | [![OpenSSF
Scorecard](https://api.securityscorecards.dev/projects/github.com/docker/build-push-action/badge)](https://securityscorecards.dev/viewer/?uri=github.com/docker/build-push-action)
|

---

### Release Notes

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

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

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

</details>

---

### Configuration

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every weekday,every weekend" (UTC), Automerge - At any time (no schedule
defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

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---

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---

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.github/workflows/solidity.yml

@@ -207,7 +207,7 @@ jobs:
             type=sha
 
       - name: Build and push
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         id: build-and-push
         with:
           platforms: linux/amd64,linux/arm64