T9304: Fix workflow that checks unused imports [circinus]

[asklymenko]

Change Summary

it is required to fix this workflow to work correctly after GitHub "actions/github-script" update from version "v4" to version "v9". It currently fails with the following error: "TypeError: Cannot read properties of undefined (reading 'listFiles')"

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Other (please describe): CI maintenance

Related Task(s)

• https://vyos.dev/T9304

Related PR(s)

Proposed changes

How to test

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly

[coderabbitai]

Important

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⚙️ Run configuration

Configuration used: Central YAML (base), Organization UI (inherited)

Review profile: CHILL

Plan: Advanced

Run ID: a902acbf-38b9-45d6-82a4-e624af643f4b

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[asklymenko]

It is the same change as we made to this file for "production" branch.

[sever-sever]

Fix CI workflow