chore(deps): update docker/metadata-action action to v6 (#180)

This PR contains the following updates:

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

---

### Release Notes

<details>
<summary>docker/metadata-action (docker/metadata-action)</summary>

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

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

</details>

---

### Configuration

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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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View the [repository job
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.github/workflows/ci.yml

@@ -75,7 +75,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - id: meta
-        uses: docker/metadata-action@c299e40c65443455700f0fdfc63efafe5b349051 # v5
+        uses: docker/metadata-action@030e881283bb7a6894de51c315a6bfe6a94e05cf # v6
         with:
           images: ghcr.io/platform-mesh/${{ matrix.image }}
           tags: |