test(bun): Fix failing test after span.isRecording change

[Lms24]

Not sure why our Bun Unit Tests were still passing but locally as well as in CI somehow
else (weird) this test failed.

This failed in CI but I see no failed jobs 🤔

cc @mydea I think the test fix should be correct - in the finishTransaction test, the
span is already finished (hence, isRecording returns false) but spanIsSampled should
still be true.

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser (incl. Tracing, Replay, Feedback) - Webpack (gzipped)	76.98 KB (+0.13% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack (gzipped)	68.36 KB (+0.17% 🔺)
@sentry/browser (incl. Tracing, Replay) - Webpack with treeshaking flags (gzipped)	61.99 KB (+0.19% 🔺)
@sentry/browser (incl. Tracing) - Webpack (gzipped)	32.38 KB (+0.31% 🔺)
@sentry/browser (incl. Feedback) - Webpack (gzipped)	30.98 KB (+0.79% 🔺)
@sentry/browser - Webpack (gzipped)	22.31 KB (+0.96% 🔺)
@sentry/browser (incl. Tracing, Replay, Feedback) - ES6 CDN Bundle (gzipped)	74.61 KB (+0.06% 🔺)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (gzipped)	66.26 KB (+0.09% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (gzipped)	32.07 KB (+0.11% 🔺)
@sentry/browser - ES6 CDN Bundle (gzipped)	23.9 KB (+0.66% 🔺)
@sentry/browser (incl. Tracing, Replay) - ES6 CDN Bundle (minified & uncompressed)	208.7 KB (+0.01% 🔺)
@sentry/browser (incl. Tracing) - ES6 CDN Bundle (minified & uncompressed)	96.75 KB (+0.02% 🔺)
@sentry/browser - ES6 CDN Bundle (minified & uncompressed)	71.35 KB (+0.57% 🔺)
@sentry/browser (incl. Tracing) - ES5 CDN Bundle (gzipped)	35.04 KB (+0.13% 🔺)
@sentry/react (incl. Tracing, Replay) - Webpack (gzipped)	68.72 KB (+0.14% 🔺)
@sentry/react - Webpack (gzipped)	22.35 KB (+1% 🔺)
@sentry/nextjs Client (incl. Tracing, Replay) - Webpack (gzipped)	85.37 KB (+0.02% 🔺)
@sentry/nextjs Client - Webpack (gzipped)	49.5 KB (+0.05% 🔺)
@sentry-internal/feedback - Webpack (gzipped)	17.01 KB (+1.53% 🔺)

[mydea]

weird that this is reported so weirdly... 🤔