feat: Remove deprecated kubeProxyVersion property

[KonradPietocha]

Description

Changes proposed in this pull request:

• Removed deprecated kubeProxyVersion field,
• For the Nodes version column, replace the value from deprecated kubeProxyVersion with the value from the kubeletVersion field (it's the same value)

Related issue(s)

Closes #3521

Definition of done

• The PR's title starts with one of the following prefixes:
  • feat: A new feature
  • fix: A bug fix
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  • chore: Maintainance changes to the build process or auxiliary tools, libraries, workflows, etc.
• Related issues are linked. To link internal trackers, use the issue IDs like backlog#4567
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