CVE-2026-54160: fallo de gravedad alta en networkupstools nut

Network UPS Tools is a collection of programs which provide a common interface for monitoring and administering UPS, PDU and SCD hardware. Prior to commits 658b24e and 1aa31d1, the GitHub Actions script used to prepare NUT tarballs and update GitHub Checks statuses and PR comments about it was mis-structured in terms of mixing code running with higher privileges (single-use token generated with write permissions) and untrusted inputs (PR source branch). A malicious PR run from a fork could extract the GITHUB_TOKEN value. It could potentially be abused while it was valid (while the GHA job ran) to manipulate Git repository contents, commit checks/statuses, or issue/PR comments, according to permissions it was issued with. This issue has been patched via commits 658b24e and 1aa31d1.