feat(tracing): Revert browser tracing integration changes

[mydea]

Due to #10327, this reverts changes to the browser tracing integration as we're actually going to replace this differently.

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser (incl. Tracing, Replay, Feedback) - Webpack (gzipped)	77.78 KB (-0.09% 🔽)
@sentry/browser (incl. Tracing, Replay) - Webpack (gzipped)	68.96 KB (-0.09% 🔽)
@sentry/browser (incl. Tracing, Replay with Canvas) - Webpack (gzipped)	72.85 KB (-0.1% 🔽)
@sentry/browser (incl. Tracing, Replay) - Webpack with treeshaking flags (gzipped)	62.59 KB (-0.1% 🔽)
@sentry/browser (incl. Tracing) - Webpack (gzipped)	32.98 KB (-0.17% 🔽)
@sentry/browser (incl. Feedback) - Webpack (gzipped)	31.25 KB (0%)
@sentry/browser (incl. sendFeedback) - Webpack (gzipped)	31.26 KB (0%)
@sentry/browser - Webpack (gzipped)	22.5 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback) - ES6 CDN Bundle (gzipped)	75.53 KB (-0.11% 🔽)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (gzipped)	67.09 KB (-0.12% 🔽)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (gzipped)	32.93 KB (-0.22% 🔽)
@sentry/browser - ES6 CDN Bundle (gzipped)	24.43 KB (-0.06% 🔽)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (minified & uncompressed)	211.3 KB (-0.15% 🔽)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (minified & uncompressed)	99.29 KB (-0.32% 🔽)
@sentry/browser - ES6 CDN Bundle (minified & uncompressed)	73.08 KB (-0.08% 🔽)
@sentry/browser (incl. Tracing) - ES5 CDN Bundle (gzipped)	36 KB (-0.26% 🔽)
@sentry/react (incl. Tracing, Replay) - Webpack (gzipped)	69.39 KB (-0.09% 🔽)
@sentry/react - Webpack (gzipped)	22.55 KB (0%)
@sentry/nextjs Client (incl. Tracing, Replay) - Webpack (gzipped)	86.03 KB (-0.09% 🔽)
@sentry/nextjs Client - Webpack (gzipped)	50.32 KB (-0.14% 🔽)
@sentry-internal/feedback - Webpack (gzipped)	17.21 KB (0%)