feat(core): Deprecate Span.parentSpanId

[Lms24]

Deprecate the Span.parentSpanId field on the interface and class.

This required only a couple of code replacements and a bunch of test adjustments. Also went ahead and changed the integration test event type in the tests I was modifying (#10240).

ref #10184

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser (incl. Tracing, Replay, Feedback) - Webpack (gzipped)	77.64 KB (+0.03% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack (gzipped)	68.91 KB (+0.04% 🔺)
@sentry/browser (incl. Tracing, Replay with Canvas) - Webpack (gzipped)	72.79 KB (+0.03% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack with treeshaking flags (gzipped)	62.54 KB (+0.03% 🔺)
@sentry/browser (incl. Tracing) - Webpack (gzipped)	32.92 KB (+0.08% 🔺)
@sentry/browser (incl. Feedback) - Webpack (gzipped)	31.16 KB (0%)
@sentry/browser (incl. sendFeedback) - Webpack (gzipped)	31.16 KB (0%)
@sentry/browser - Webpack (gzipped)	22.51 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback) - ES6 CDN Bundle (gzipped)	75.22 KB (+0.01% 🔺)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (gzipped)	66.84 KB (+0.03% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (gzipped)	32.7 KB (+0.06% 🔺)
@sentry/browser - ES6 CDN Bundle (gzipped)	24.23 KB (0%)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (minified & uncompressed)	210.59 KB (+0.02% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (minified & uncompressed)	98.57 KB (+0.03% 🔺)
@sentry/browser - ES6 CDN Bundle (minified & uncompressed)	72.52 KB (0%)
@sentry/browser (incl. Tracing) - ES5 CDN Bundle (gzipped)	35.74 KB (+0.06% 🔺)
@sentry/react (incl. Tracing, Replay) - Webpack (gzipped)	69.33 KB (+0.04% 🔺)
@sentry/react - Webpack (gzipped)	22.55 KB (0%)
@sentry/nextjs Client (incl. Tracing, Replay) - Webpack (gzipped)	85.92 KB (+0.04% 🔺)
@sentry/nextjs Client - Webpack (gzipped)	50.03 KB (+0.05% 🔺)
@sentry-internal/feedback - Webpack (gzipped)	17.14 KB (0%)