fix(node): Do not assert in vendored proxy code (v7 backport)

[timfish]

Closes #11002

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser (incl. Tracing, Replay, Feedback) - Webpack (gzipped)	78.71 KB (+0.01% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack (gzipped)	69.87 KB (0%)
@sentry/browser (incl. Tracing, Replay with Canvas) - Webpack (gzipped)	73.83 KB (0%)
@sentry/browser (incl. Tracing, Replay) - Webpack with treeshaking flags (gzipped)	63.48 KB (0%)
@sentry/browser (incl. Tracing) - Webpack (gzipped)	33.84 KB (0%)
@sentry/browser (incl. browserTracingIntegration) - Webpack (gzipped)	34.88 KB (+0.01% 🔺)
@sentry/browser (incl. Feedback) - Webpack (gzipped)	31.44 KB (0%)
@sentry/browser (incl. sendFeedback) - Webpack (gzipped)	31.45 KB (0%)
@sentry/browser - Webpack (gzipped)	22.68 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback) - ES6 CDN Bundle (gzipped)	76.98 KB (0%)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (gzipped)	68.4 KB (0%)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (gzipped)	34.2 KB (0%)
@sentry/browser - ES6 CDN Bundle (gzipped)	25.11 KB (0%)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (minified & uncompressed)	215.54 KB (0%)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (minified & uncompressed)	103.35 KB (0%)
@sentry/browser - ES6 CDN Bundle (minified & uncompressed)	75.38 KB (0%)
@sentry/browser (incl. Tracing) - ES5 CDN Bundle (gzipped)	37.38 KB (+0.02% 🔺)
@sentry/react (incl. Tracing, Replay) - Webpack (gzipped)	70.25 KB (0%)
@sentry/react - Webpack (gzipped)	22.71 KB (0%)
@sentry/nextjs Client (incl. Tracing, Replay) - Webpack (gzipped)	89.13 KB (+0.04% 🔺)
@sentry/nextjs Client - Webpack (gzipped)	53.3 KB (+0.05% 🔺)
@sentry-internal/feedback - Webpack (gzipped)	17.28 KB (0%)

[Lms24]

Thanks!