ci: set GitHub Actions user to prevent brew command failure

[zyfy29]

close #3886

[Copilot]

Pull Request Overview

This PR addresses a GitHub Actions workflow failure by configuring Git user identity before running brew commands. The change prevents the brew installation process from failing due to missing Git user configuration.

• Adds Git global user configuration in the GitHub Actions workflow
• Sets a standard "GitHub Actions Bot" identity with appropriate email

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[AkihiroSuda]

Please squash the commits
https://lima-vm.io/docs/dev/git/#squashing-commits

[AkihiroSuda]

Thanks