Potential fix for code scanning alert no. 8: Workflow does not contain permissions (#13670)

* Potential fix for code scanning alert no. 8: Workflow does not contain permissions

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>
Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

* Update merge-main-into-prs.yml

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

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Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>
Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>