Update data-platform-workflows to v18

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
canonical/data-platform-workflows	action	major	v17 -> v18
canonical/data-platform-workflows	action	major	v17.0.1 -> v18.0.0

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Release Notes

canonical/data-platform-workflows (canonical/data-platform-workflows)

### [`v18`](https://togithub.com/canonical/data-platform-workflows/compare/v18.0.0...v18.0.0) [Compare Source](https://togithub.com/canonical/data-platform-workflows/compare/v17...v18)

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