ci: setup project in post-release

[barmac]

Proposed Changes

This is required for the translations update. Cf. https://github.com/bpmn-io/bpmn-js/actions/runs/12948699811

Checklist

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• Brief textual description of the changes present
• Visual demo attached
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• Related issue linked via Closes {LINK_TO_ISSUE} or Related to {LINK_TO_ISSUE}