chore(deps): update woodpeckerci/plugin-docker-buildx docker tag to v6 (#39)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [woodpeckerci/plugin-docker-buildx](https://codeberg.org/woodpecker-plugins/docker-buildx) ([source](https://codeberg.org/woodpecker-plugins/docker-buildx.git)) | major | `5.2.2` -> `6.0.0` |

---

### Release Notes

<details>
<summary>woodpecker-plugins/docker-buildx (woodpeckerci/plugin-docker-buildx)</summary>

### [`v6.0.0`](https://codeberg.org/woodpecker-plugins/docker-buildx/blob/HEAD/CHANGELOG.md#600---2025-05-02)

[Compare Source](https://codeberg.org/woodpecker-plugins/docker-buildx/compare/v5.2.2...v6.0.0)

##### ❤️ Thanks to all contributors! ❤️

[@&#8203;pat-s](https://github.com/pat-s), [@&#8203;woodpecker-bot](https://github.com/woodpecker-bot), [@&#8203;xoxys](https://github.com/xoxys)

##### 💥 Breaking changes

-   Use custom flags to support from_secret and escaping \[[#&#8203;229](https://codeberg.org/woodpecker-plugins/docker-buildx/pulls/229)]

##### 📚 Documentation

-   chore: add tests for tag parsing \[[#&#8203;228](https://codeberg.org/woodpecker-plugins/docker-buildx/pulls/228)]

##### 📦️ Dependency

-   fix(deps): update module github.com/urfave/cli/v3 to v3.3.2 \[[#&#8203;235](https://codeberg.org/woodpecker-plugins/docker-buildx/pulls/235)]
-   chore(deps): update woodpeckerci/plugin-docker-buildx docker tag to v5.2.2 \[[#&#8203;225](https://codeberg.org/woodpecker-plugins/docker-buildx/pulls/225)]

##### Misc

-   chore: remove CODEOWNERS to avoid confusion ([82de34d](82de34de99))
-   fix(deps): update module github.com/go-git/go-git/v5 to v5.16.0 ([12a6790](12a67908e6))
-   chore(deps): update docker/buildx-bin docker tag to v0.23.0 ([053af77](053af77a3a))
-   chore(deps): update docker.io/woodpeckerci/plugin-ready-release-go docker tag to v3.2.0 ([7694208](7694208424))
-   chore(deps): update docker docker tag to v28.1.1 ([9edff8f](9edff8fa43))
-   fix(deps): update module github.com/pelletier/go-toml/v2 to v2.2.4 ([152d91a](152d91a3a1))
-   fix(deps): update module github.com/aws/aws-sdk-go to v1.55.7 ([c641ced](c641ced5d9))
-   fix(deps): update module github.com/urfave/cli/v3 to v3.1.1 ([064a419](064a419fe2))
-   chore(deps): update dependency go to v1.24.2 ([da71aa3](da71aa3c05))
-   chore(deps): update docker.io/woodpeckerci/plugin-ready-release-go docker tag to v3.1.4 ([75d9090](75d909067d))
-   chore(deps): update docker docker tag to v28.0.4 ([bcd9b33](bcd9b33e4c))

</details>

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Reviewed-on: #39
Co-authored-by: renovate-bot <renovate@ocram85.com>
Co-committed-by: renovate-bot <renovate@ocram85.com>

.woodpecker/ci.yml

@@ -5,7 +5,7 @@ when:
       - ${CI_REPO_DEFAULT_BRANCH}
 
 variables:
-  - &build_plugin 'woodpeckerci/plugin-docker-buildx:5.2.2'
+  - &build_plugin 'woodpeckerci/plugin-docker-buildx:6.0.0'
   # deployment targets
   # TODO: Disabled docker hub target until first release is ready / Rate Limits
   - &publish_repos 'ocram85/plugin-gitea-package,gitea.ocram85.com/plugins/gitea-package'