test(react): Remove duplicated test mock

[s1gr1d]

The getActiveSpan mock calls actual.getActiveSpan() and immediately assigns to the returned span without guarding
against undefined. When the router subscriber fires outside an active span context, span is undefined and the property assignment throws a TypeError.

Additionally, there are two vi.mock('@sentry/core') declarations for the same module; the first (lines 66-73) is dead code since the second one overrides it.

Closes#20199

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

📋 Changelog Preview

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New Features ✨

Core

• Add enableTruncation option to Google GenAI integration by andreiborza in #20184
• Add enableTruncation option to Anthropic AI integration by andreiborza in #20181
• Add enableTruncation option to LangGraph integration by andreiborza in #20183
• Add enableTruncation option to LangChain integration by andreiborza in #20182
• Add enableTruncation option to OpenAI integration by andreiborza in #20167
• Export a reusable function to add tracing headers by JPeer264 in #20076

Deps

• Bump axios from 1.13.5 to 1.15.0 by dependabot in #20180
• Bump hono from 4.12.7 to 4.12.12 by dependabot in #20118
• Bump defu from 6.1.4 to 6.1.6 by dependabot in #20104

Bug Fixes 🐛

• (deno) Avoid inferring invalid span op from Deno tracer by Lms24 in #20128
• (e2e) Add op check to waitForTransaction in React Router e2e tests by copilot-swe-agent in #20193

Internal Changes 🔧

Deps

• Bump hono from 4.12.7 to 4.12.12 in /dev-packages/e2e-tests/test-applications/cloudflare-hono by dependabot in #20119
• Bump axios from 1.13.5 to 1.15.0 in /dev-packages/e2e-tests/test-applications/nestjs-basic by dependabot in #20179

Other

• (bugbot) Add rules to flag test-flake-provoking patterns by Lms24 in #20192
• (deps-dev) Bump vite from 7.2.0 to 7.3.2 in /dev-packages/e2e-tests/test-applications/tanstackstart-react by dependabot in #20107

• (react) Remove duplicated test mock by s1gr1d in #20200

• (size-limit) Bump failing size limit scenario by Lms24 in #20186

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[github-actions]

size-limit report 📦

⚠️Warning: Base artifact is not the latest one, because the latest workflow run is not done yet. This may lead to incorrect results. Try to re-run all tests to get up to date results.

Path	Size	% Change	Change
@sentry/browser	25.72 kB	-	-
@sentry/browser - with treeshaking flags	24.21 kB	-	-
@sentry/browser (incl. Tracing)	42.73 kB	-	-
@sentry/browser (incl. Tracing, Profiling)	47.35 kB	-	-
@sentry/browser (incl. Tracing, Replay)	81.54 kB	-	-
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	71.11 kB	-	-
@sentry/browser (incl. Tracing, Replay with Canvas)	86.25 kB	-	-
@sentry/browser (incl. Tracing, Replay, Feedback)	98.45 kB	-	-
@sentry/browser (incl. Feedback)	42.51 kB	-	-
@sentry/browser (incl. sendFeedback)	30.39 kB	-	-
@sentry/browser (incl. FeedbackAsync)	35.38 kB	-	-
@sentry/browser (incl. Metrics)	27.04 kB	-	-
@sentry/browser (incl. Logs)	27.18 kB	-	-
@sentry/browser (incl. Metrics & Logs)	27.86 kB	-	-
@sentry/react	27.48 kB	-	-
@sentry/react (incl. Tracing)	45.05 kB	-	-
@sentry/vue	30.56 kB	-	-
@sentry/vue (incl. Tracing)	44.59 kB	-	-
@sentry/svelte	25.74 kB	-	-
CDN Bundle	28.41 kB	-	-
CDN Bundle (incl. Tracing)	43.75 kB	-	-
CDN Bundle (incl. Logs, Metrics)	29.78 kB	-	-
CDN Bundle (incl. Tracing, Logs, Metrics)	44.83 kB	-	-
CDN Bundle (incl. Replay, Logs, Metrics)	68.59 kB	-	-
CDN Bundle (incl. Tracing, Replay)	80.64 kB	-	-
CDN Bundle (incl. Tracing, Replay, Logs, Metrics)	81.66 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback)	86.17 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics)	87.2 kB	-	-
CDN Bundle - uncompressed	82.99 kB	-	-
CDN Bundle (incl. Tracing) - uncompressed	129.77 kB	-	-
CDN Bundle (incl. Logs, Metrics) - uncompressed	87.14 kB	-	-
CDN Bundle (incl. Tracing, Logs, Metrics) - uncompressed	133.19 kB	-	-
CDN Bundle (incl. Replay, Logs, Metrics) - uncompressed	210.12 kB	-	-
CDN Bundle (incl. Tracing, Replay) - uncompressed	246.65 kB	-	-
CDN Bundle (incl. Tracing, Replay, Logs, Metrics) - uncompressed	250.05 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	259.56 kB	-	-
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics) - uncompressed	262.95 kB	-	-
@sentry/nextjs (client)	47.47 kB	-	-
@sentry/sveltekit (client)	43.2 kB	-	-
@sentry/node-core	57.86 kB	+0.02%	+7 B 🔺
@sentry/node	174.86 kB	+0.03%	+41 B 🔺
@sentry/node - without tracing	97.97 kB	+0.03%	+22 B 🔺
@sentry/aws-serverless	115.22 kB	+0.02%	+19 B 🔺

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