Update docker/setup-buildx-action action to v4 (#11)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [docker/setup-buildx-action](https://github.com/docker/setup-buildx-action) | action | major | `v3` → `v4` |

---

### Release Notes

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

### [`v4.1.0`](https://github.com/docker/setup-buildx-action/releases/tag/v4.1.0)

[Compare Source](docker/setup-buildx-action@v4...v4.1.0)

- Bump [@&#8203;docker/actions-toolkit](https://github.com/docker/actions-toolkit) from 0.79.0 to 0.90.0 in [#&#8203;489](docker/setup-buildx-action#489)
- Bump brace-expansion from 1.1.12 to 5.0.6 in [#&#8203;547](docker/setup-buildx-action#547) [#&#8203;508](docker/setup-buildx-action#508)
- Bump fast-xml-builder from 1.0.0 to 1.2.0 in [#&#8203;540](docker/setup-buildx-action#540)
- Bump fast-xml-parser from 5.4.2 to 5.8.0 in [#&#8203;496](docker/setup-buildx-action#496)
- Bump flatted from 3.3.3 to 3.4.2 in [#&#8203;499](docker/setup-buildx-action#499)
- Bump glob from 10.3.12 to 13.0.6 in [#&#8203;495](docker/setup-buildx-action#495)
- Bump handlebars from 4.7.8 to 4.7.9 in [#&#8203;504](docker/setup-buildx-action#504)
- Bump lodash from 4.17.23 to 4.18.1 in [#&#8203;523](docker/setup-buildx-action#523)
- Bump picomatch from 4.0.3 to 4.0.4 in [#&#8203;503](docker/setup-buildx-action#503)
- Bump postcss from 8.5.6 to 8.5.10 in [#&#8203;537](docker/setup-buildx-action#537)
- Bump tar from 6.2.1 to 7.5.15 in [#&#8203;545](docker/setup-buildx-action#545)
- Bump undici from 6.23.0 to 6.25.0 in [#&#8203;492](docker/setup-buildx-action#492)
- Bump vite from 7.3.1 to 7.3.2 in [#&#8203;520](docker/setup-buildx-action#520)

**Full Changelog**: <docker/setup-buildx-action@v4.0.0...v4.1.0>

### [`v4.0.0`](https://github.com/docker/setup-buildx-action/releases/tag/v4.0.0)

[Compare Source](docker/setup-buildx-action@v4...v4)

- Node 24 as default runtime (requires [Actions Runner v2.327.1](https://github.com/actions/runner/releases/tag/v2.327.1) or later) by [@&#8203;crazy-max](https://github.com/crazy-max) in [#&#8203;483](docker/setup-buildx-action#483)
- Remove deprecated inputs/outputs by [@&#8203;crazy-max](https://github.com/crazy-max) in [#&#8203;464](docker/setup-buildx-action#464)
- Switch to ESM and update config/test wiring by [@&#8203;crazy-max](https://github.com/crazy-max) in [#&#8203;481](docker/setup-buildx-action#481)
- Bump [@&#8203;actions/core](https://github.com/actions/core) from 1.11.1 to 3.0.0 in [#&#8203;475](docker/setup-buildx-action#475)
- Bump [@&#8203;docker/actions-toolkit](https://github.com/docker/actions-toolkit) from 0.63.0 to 0.79.0 in [#&#8203;482](docker/setup-buildx-action#482) [#&#8203;485](docker/setup-buildx-action#485)
- Bump js-yaml from 4.1.0 to 4.1.1 in [#&#8203;452](docker/setup-buildx-action#452)
- Bump lodash from 4.17.21 to 4.17.23 in [#&#8203;472](docker/setup-buildx-action#472)
- Bump minimatch from 3.1.2 to 3.1.5 in [#&#8203;480](docker/setup-buildx-action#480)

**Full Changelog**: <docker/setup-buildx-action@v3.12.0...v4.0.0>

### [`v4`](docker/setup-buildx-action@v3.12.0...v4)

[Compare Source](docker/setup-buildx-action@v3.12.0...v4)

</details>

---

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---

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---

This PR has been generated by [Mend Renovate](https://github.com/renovatebot/renovate).
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Co-authored-by: hoodn <hood.noah@gmail.com>
Reviewed-on: https://gitea.k3s.noah-hood.io/hoodn/certmanager-porkbun-webhook/pulls/11
Co-authored-by: renovate-bot <renovate-bot@example.local>
Co-committed-by: renovate-bot <renovate-bot@example.local>

Author: renovate-bot

.gitea/workflows/ci.yaml

@@ -27,7 +27,7 @@ jobs:
         run: go build ./...
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Docker build (no push)
         uses: docker/build-push-action@v7

.gitea/workflows/release.yaml

@@ -24,7 +24,7 @@ jobs:
         uses: actions/checkout@v6
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@v4
 
       - name: Log in to Gitea container registry
         uses: docker/login-action@v3