Replace CaretDownIcon with RhUiCaretDownIcon

[nicolethoen]

Summary

Replace all usages of the legacy FA CaretDownIcon with the RH brand RhUiCaretDownIcon.

Linked PR

• chore(CaretDownIcon): Replace all usages of CaretDownIcon with RhUiCaretDownIcon #12368

Acceptance Criteria

• All CaretDownIcon imports replaced with RhUiCaretDownIcon

• No broken links or references as a result of the change

• Tests pass

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Jira Issue: PF-4085

[coderabbitai]

🔗 Related PRs

#12366 - chore(ExternalLinkSquareAltIcon): Replace all usages of ExternalLinkSquareAltIcon with RhUiExternalLinkFillIcon [merged]
#12371 - chore(Star Icons): Replace all star FA icons with RH brand star icons [merged]
#12376 - chore(EmptyState): Update use a RH brand icon in tests [merged]
#12379 - chore(OutlinedQuestionCircleIcon): Update uses of OutlinedQuestionCircleIcon to use RhUiQuestionMarkCircleIcon [merged]
#12387 - feat: update rhds icons to 2.2.0 [merged]

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