test: Refactor utils into `@sentry-internal/test-utils`

[mydea]

Re-use this for playwright config in E2E tests.

Now, instead of repeating the whole playwright config, we can import the util from @sentry-internal/test-utils and pass it some config.

I left the places where do not yet use the proxy, because for simplicity I built the util in a way that assumes the proxy (you can override it, but I figured not worth it for stuff that we will refactor soon anyhow).

While at it, I also streamlined the playwright version used everywhere to an up-to-date version.

[github-actions[bot]]

size-limit report 📦

Path	Size
@sentry/browser	21.74 KB (0%)
@sentry/browser (incl. Tracing)	32.76 KB (+0.1% 🔺)
@sentry/browser (incl. Tracing, Replay)	68.33 KB (+0.05% 🔺)
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	61.64 KB (+0.05% 🔺)
@sentry/browser (incl. Tracing, Replay with Canvas)	72.39 KB (+0.05% 🔺)
@sentry/browser (incl. Tracing, Replay, Feedback)	84.5 KB (+0.04% 🔺)
@sentry/browser (incl. Tracing, Replay, Feedback, metrics)	86.35 KB (+0.04% 🔺)
@sentry/browser (incl. metrics)	25.92 KB (+0.02% 🔺)
@sentry/browser (incl. Feedback)	37.9 KB (0%)
@sentry/browser (incl. sendFeedback)	26.32 KB (0%)
@sentry/browser (incl. FeedbackAsync)	30.86 KB (0%)
@sentry/react	24.51 KB (0%)
@sentry/react (incl. Tracing)	35.8 KB (+0.07% 🔺)
@sentry/vue	25.73 KB (+0.02% 🔺)
@sentry/vue (incl. Tracing)	34.59 KB (+0.08% 🔺)
@sentry/svelte	21.87 KB (0%)
CDN Bundle	23.11 KB (0%)
CDN Bundle (incl. Tracing)	34.5 KB (+0.12% 🔺)
CDN Bundle (incl. Tracing, Replay)	68.42 KB (+0.05% 🔺)
CDN Bundle (incl. Tracing, Replay, Feedback)	73.6 KB (+0.05% 🔺)
CDN Bundle - uncompressed	68 KB (0%)
CDN Bundle (incl. Tracing) - uncompressed	102.16 KB (+0.06% 🔺)
CDN Bundle (incl. Tracing, Replay) - uncompressed	212.05 KB (+0.03% 🔺)
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	224.52 KB (+0.03% 🔺)
@sentry/nextjs (client)	35.14 KB (+0.06% 🔺)
@sentry/sveltekit (client)	33.39 KB (+0.08% 🔺)
@sentry/node	115.24 KB (0%)
@sentry/aws-serverless	103.72 KB (0%)