Disallow Server Action submissions from privacy-sensitive contexts (#91478)
See:
https://github.com/vercel/next.js/security/advisories/GHSA-mq59-m269-xvcx
and [16.1.7](https://github.com/vercel/next.js/releases/tag/v16.1.7)
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Co-authored-by: Sebastian "Sebbie" Silbermann <sebastian.silbermann@vercel.com>