Remove deprecated Defaulter and Validator interfaces

[Karthik-K-N]

/kind feature
/area provider/ibmcloud

User Story

What would you like to be added?

controller-runtime has removed the admission.Defaulter and admission.Validator interfaces as of v0.20.0 (kubernetes-sigs/controller-runtime#2877)

cluster-api v1.10 uses a version of controller-runtime that no longer has these present.

Example: "As a [developer/user/operator], I would like to [high-level description] for [reasons]."

Detailed Feature Description

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Context & Motivation

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Proposed Solution

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Alternatives Considered

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Additional Information

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