kip-227: update byzantine filtering formula

[ian0371]

Proposed changes

• update byzantine filtering formula as per vrank: add vrank module kaia#879

Types of changes

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• Bugfix
• KIP Proposal
• KIP Improvement

Checklist

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• Used the suggested template: https://github.com/kaiachain/KIPs/blob/main/kip-template.md
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Related issues

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Further comments

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