[Docs] add note to clarify use of Link when clearing preview cookies (issue #34129)

[mattyocode]

Add note that explains the need to pass prefetch={false} to Link component to prevent clearing cookies accidentally
(responding to issue "Docs: potential preview-mode error on production build #34129").

Note as follows:

Note: If calling this route using Link component, you must pass in prefetch={false} to prevent calling clearPreviewData during prefetch.

Bug

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Feature

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Documentation / Examples

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