docs(fetch): update wording on conflicting cache and revalidate options (#80591)
Clarifies that using conflicting options such as `{ revalidate: 3600,
cache: 'no-store' }` results in a warning in the terminal rather than an
error.
This change helps accurately reflect the current runtime behavior and
avoids misleading readers into expecting a hard failure.
The update improves developer understanding when configuring fetch/cache
strategies in their applications.
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Co-authored-by: Joseph <joseph.chamochumbi@vercel.com>