Fix External Audit Storage CTA condition

[mcbattirola]

featureEnabled was not properly set, so users with EAS enabled would see a locked button on the CTA, as if they didn't have access to the feature.

This didn't affect the actual button to add the integration, just the CTA.

I've also fixed the useEffect dependency array condition, as ctx.hasExternalAuditStorage was missing, and cfg.isCloud shouldn't be added since it didn't came through a prop or hook

part of #42119

[github-actions]

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[public-teleport-github-review-bot]

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