Add Author Feedback label automatically (#28484)

Summary:
Improve issue triage by automatically adding the "Needs: Author Feedback" label.

NOTE: The old label-actions app should be disabled when this PR is merged: https://github.com/apps/label-actions/installations/7445225

## Changelog

[Internal] - Issue Triage
Pull Request resolved: https://github.com/facebook/react-native/pull/28484

Test Plan: Verified the same `label-actions.yml` and workflow config on a private repo.

Reviewed By: cpojer

Differential Revision: D20817443

Pulled By: hramos

fbshipit-source-id: 39732dd67509c9fb9cf6ff7306913f5ec088266d