build(replay): Generate Replay CDN bundles

[Lms24]

This PR adds a rollup config to generate an addon CDN bundle for the Replay integration. Usage of this bundle is identical to our other integration CDN bundles in the sense that the bundle has to be added in addition to the regular browser (or browser+tracing) bundle.

As of this PR, three bundles will be generated into build/bundles:

• replay.js (the unminified bundle with debug output)
• replay.min.js(the minified bundle without debug output)
• replay.debug.min.js (the minified bundle with debug output)

For now, we'll only generate ES6 bundles but we can add ES5 versions if requested later on.

ref #6362

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser - ES5 CDN Bundle (gzipped + minified)	19.57 KB (-0.02% 🔽)
@sentry/browser - ES5 CDN Bundle (minified)	60.59 KB (0%)
@sentry/browser - ES6 CDN Bundle (gzipped + minified)	18.36 KB (0%)
@sentry/browser - ES6 CDN Bundle (minified)	54.15 KB (0%)
@sentry/browser - Webpack (gzipped + minified)	20.12 KB (0%)
@sentry/browser - Webpack (minified)	65.75 KB (0%)
@sentry/react - Webpack (gzipped + minified)	20.14 KB (0%)
@sentry/nextjs Client - Webpack (gzipped + minified)	45.95 KB (0%)
@sentry/browser + @sentry/tracing - ES5 CDN Bundle (gzipped + minified)	26.41 KB (-0.01% 🔽)
@sentry/browser + @sentry/tracing - ES6 CDN Bundle (gzipped + minified)	24.85 KB (+0.02% 🔺)
@sentry/replay index.js	0 B (removed)
@sentry/replay - Webpack (gzipped + minified)	37.05 KB (0%)
@sentry/replay - Webpack (minified)	0 B (removed)
@sentry/replay ES6 CDN Bundle (gzipped + minified)	41.58 KB (added)

[lobsterkatie]

A few small questions, but otherwise LGTM!