Add getMultipleSentryRequests helper.

[onurtemizkan]

getSentryRequest helper of integration tests, only captures the first event that's sent.

To capture multiple events in tests, we either need to use beforeSend hook inside initialization script, to populate a global events array, and then use getSentryEvents in tests to assert events, or replace getSentryEvents with this implementation and wait for collection of multiple requests.

cc: @AbhiPrasad

[github-actions]

size-limit report

Path	Base Size (a5e7ff6)	Current Size	Change
@sentry/browser - CDN Bundle (gzipped)	20.24 KB	20.24 KB	+0.02% 🔺
@sentry/browser - CDN Bundle (minified)	64.29 KB	64.29 KB	+0.01% 🔺
@sentry/browser - Webpack	22.22 KB	22.22 KB	0%
@sentry/browser - Webpack - gzip = false	75.7 KB	75.7 KB	0%
@sentry/react - Webpack	22.25 KB	22.25 KB	0%
@sentry/nextjs Client - Webpack	46.35 KB	46.35 KB	0%
@sentry/browser + @sentry/tracing - CDN Bundle (gzipped)	28.34 KB	28.34 KB	+0.02% 🔺