feat: safelist common string in react proptypes from secret detection

[aitchiss]

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Summary

Fixes https://linear.app/netlify/issue/WRFL-2579/false-positives-with-env-var-names-esp-with-secret

This string is commonly bundled into apps using react proptypes, let's make sure we ignore

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[github-actions]

This pull request adds or modifies JavaScript (.js, .cjs, .mjs) files.
Consider converting them to TypeScript.