test(core): Add integration test for captureUserFeedback on captureException and captureMessage

[Lms24]

Added two tests to demonstrate correct behavior of captureUserFeedback when it's called in beforeSend as described in the docs.

Trying to rule out SDK issues for #10229. Given the tests pass, I suspect something isn't working on the Sentry backend when ingesting the feedback.

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser (incl. Tracing, Replay, Feedback) - Webpack (gzipped)	77.37 KB (0%)
@sentry/browser (incl. Tracing, Replay) - Webpack (gzipped)	68.67 KB (0%)
@sentry/browser (incl. Tracing, Replay with Canvas) - Webpack (gzipped)	72.54 KB (+0.08% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack with treeshaking flags (gzipped)	62.31 KB (0%)
@sentry/browser (incl. Tracing) - Webpack (gzipped)	32.67 KB (0%)
@sentry/browser (incl. Feedback) - Webpack (gzipped)	31.13 KB (0%)
@sentry/browser - Webpack (gzipped)	22.48 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback) - ES6 CDN Bundle (gzipped)	75 KB (0%)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (gzipped)	66.63 KB (0%)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (gzipped)	32.48 KB (0%)
@sentry/browser - ES6 CDN Bundle (gzipped)	24.19 KB (0%)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (minified & uncompressed)	209.91 KB (0%)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (minified & uncompressed)	97.89 KB (0%)
@sentry/browser - ES6 CDN Bundle (minified & uncompressed)	72.34 KB (0%)
@sentry/browser (incl. Tracing) - ES5 CDN Bundle (gzipped)	35.49 KB (0%)
@sentry/react (incl. Tracing, Replay) - Webpack (gzipped)	69.06 KB (0%)
@sentry/react - Webpack (gzipped)	22.52 KB (0%)
@sentry/nextjs Client (incl. Tracing, Replay) - Webpack (gzipped)	85.68 KB (0%)
@sentry/nextjs Client - Webpack (gzipped)	49.81 KB (0%)
@sentry-internal/feedback - Webpack (gzipped)	17.12 KB (+0.02% 🔺)