chore(deps): This PR adresses CVE-2025-21613 by upgrading go-git to v5.13.1

[aswinayyolath]

This PR adresses CVE-2025-21613 by upgrading go-git to v5.13.1

Description

Submitter Checklist

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• Includes unit tests
• Adds integration tests if needed.

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Reviewer Notes

• The code flow looks good.
• Unit tests and or integration tests added.

Release Notes

Describe any changes here so maintainer can include it in the release notes, or delete this block.

Examples of user facing changes:
- kaniko adds a new flag `--registry-repo` to override registry

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