chore(deps): update csaf module dependency from csaf-poc to gocsaf

[thiha-min-thant]

Description

This pull request migrates the dependency from csaf-poc/csaf_distribution to the new gocsaf/csaf module. The csaf-poc/csaf_distribution module has been moved to the official gocsaf/csaf repository, and as part of this update, the go.mod file has been modified to reflect the new module source.

Related issues

• Close Migrate csaf-poc/csaf_distribution to gocsaf/csaf #7805

Checklist

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• I've added tests that prove my fix is effective or that my feature works.
• I've updated the documentation with the relevant information (if needed).
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[knqyf263]

Thanks