test: unskip allHeaders() tests in workers.spec after chromium roll

[Dmitry Gozman (dgozman)]

Closes#39948.

[github-actions]

Test results for "MCP"

2 failed
❌ [chrome] › mcp/annotate.spec.ts:230 › should capture annotations via show --annotate @mcp-ubuntu-latest-chrome
❌ [firefox] › mcp/annotate.spec.ts:230 › should capture annotations via show --annotate @mcp-macos-latest-firefox

7758 passed, 1249 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

6 flaky

⚠️ [chromium-library] › library/video.spec.ts:476 › screencast › should capture static page in persistent context Radoslav Kirilov (@smoke) `@realtime-time-library-chromium-linux`
⚠️ [chromium-library] › library/chromium/oopif.spec.ts:282 › should click `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/video.spec.ts:680 › screencast › should capture full viewport on hidpi `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/video.spec.ts:717 › screencast › should work with video+trace `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/popup.spec.ts:260 › should not throw when click closes popup `@chromium-ubuntu-22.04-node22`
⚠️ [firefox-library] › library/heap.spec.ts:223 › should not leak workers `@firefox-ubuntu-22.04-node20`

49555 passed, 1156 skipped

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Merge workflow run.