fix(react): Revert back to jsxRuntime: 'classic' to prevent breaking react 17

[andreiborza]

Undoes some of the changes in #12204 and #12740 to fix #12608.

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser	22.28 KB (0%)
@sentry/browser (incl. Tracing)	33.43 KB (0%)
@sentry/browser (incl. Tracing, Replay)	69.18 KB (0%)
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	62.51 KB (0%)
@sentry/browser (incl. Tracing, Replay with Canvas)	73.24 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback)	85.85 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback, metrics)	87.71 KB (0%)
@sentry/browser (incl. metrics)	26.57 KB (0%)
@sentry/browser (incl. Feedback)	38.92 KB (0%)
@sentry/browser (incl. sendFeedback)	26.9 KB (0%)
@sentry/browser (incl. FeedbackAsync)	31.51 KB (0%)
@sentry/react	25.02 KB (-0.01% 🔽)
@sentry/react (incl. Tracing)	36.46 KB (-0.04% 🔽)
@sentry/vue	26.39 KB (0%)
@sentry/vue (incl. Tracing)	35.29 KB (0%)
@sentry/svelte	22.41 KB (0%)
CDN Bundle	23.49 KB (0%)
CDN Bundle (incl. Tracing)	35.18 KB (0%)
CDN Bundle (incl. Tracing, Replay)	69.28 KB (0%)
CDN Bundle (incl. Tracing, Replay, Feedback)	74.47 KB (0%)
CDN Bundle - uncompressed	68.94 KB (0%)
CDN Bundle (incl. Tracing) - uncompressed	103.96 KB (0%)
CDN Bundle (incl. Tracing, Replay) - uncompressed	214.35 KB (0%)
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	227.06 KB (0%)
@sentry/nextjs (client)	36.35 KB (0%)
@sentry/sveltekit (client)	34.07 KB (0%)
@sentry/node	130.73 KB (0%)
@sentry/node - without tracing	91.75 KB (0%)
@sentry/aws-serverless	116.92 KB (-0.01% 🔽)