feat(feedback): Add system-ui to start of font family

[billyvg]

Requested by @Jesse-Box: "...fits better with the OS the user uses"

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser (incl. Tracing, Replay, Feedback) - Webpack (gzipped)	78.14 KB (+0.02% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack (gzipped)	69.38 KB (+0.01% 🔺)
@sentry/browser (incl. Tracing, Replay with Canvas) - Webpack (gzipped)	73.3 KB (+0.09% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack with treeshaking flags (gzipped)	62.99 KB (+0.01% 🔺)
@sentry/browser (incl. Tracing) - Webpack (gzipped)	33.38 KB (0%)
@sentry/browser (incl. browserTracingIntegration) - Webpack (gzipped)	33.25 KB (0%)
@sentry/browser (incl. Feedback) - Webpack (gzipped)	31.33 KB (+0.01% 🔺)
@sentry/browser (incl. sendFeedback) - Webpack (gzipped)	31.34 KB (+0.01% 🔺)
@sentry/browser - Webpack (gzipped)	22.6 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback) - ES6 CDN Bundle (gzipped)	76.11 KB (+0.02% 🔺)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (gzipped)	67.66 KB (+0.01% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (gzipped)	33.5 KB (0%)
@sentry/browser - ES6 CDN Bundle (gzipped)	24.66 KB (0%)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (minified & uncompressed)	213.5 KB (+0.02% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (minified & uncompressed)	101.49 KB (0%)
@sentry/browser - ES6 CDN Bundle (minified & uncompressed)	74.01 KB (0%)
@sentry/browser (incl. Tracing) - ES5 CDN Bundle (gzipped)	36.63 KB (0%)
@sentry/react (incl. Tracing, Replay) - Webpack (gzipped)	69.73 KB (+0.01% 🔺)
@sentry/react - Webpack (gzipped)	22.63 KB (0%)
@sentry/nextjs Client (incl. Tracing, Replay) - Webpack (gzipped)	86.5 KB (+0.01% 🔺)
@sentry/nextjs Client - Webpack (gzipped)	50.8 KB (0%)
@sentry-internal/feedback - Webpack (gzipped)	17.21 KB (+0.03% 🔺)