💚🏁 Fix path management for Windows MLIR tests

[burgholzer]

Description

This PR aims to fix the MLIR CI that was unintentionally broken in #1139 due to our current lack of branch protection for the MLIR part of the test suite.
The necessary changes to enable that will first be added upstream in the workflows repository.

Checklist:

• The pull request only contains commits that are focused and relevant to this change.
• I have added appropriate tests that cover the new/changed functionality.
• I have updated the documentation to reflect these changes.
• I have added entries to the changelog for any noteworthy additions, changes, fixes, or removals.
• I have added migration instructions to the upgrade guide (if needed).
• The changes follow the project's style guidelines and introduce no new warnings.
• The changes are fully tested and pass the CI checks.
• I have reviewed my own code changes.