fix(yaml): escape to disambiguate yaml arrays

[pavelfeldman]

Fixes #34032

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

[github-actions]

Test results for "tests 1"

4 flaky

⚠️ [firefox-page] › page/page-evaluate.spec.ts:403:3 › should throw for too deep reference chain @firefox-ubuntu-22.04-node18
⚠️ [webkit-library] › library/proxy.spec.ts:93:11 › should proxy local network requests › by default › link-local @webkit-ubuntu-22.04-node18
⚠️ [webkit-page] › page/page-set-input-files.spec.ts:205:3 › should upload multiple large files @webkit-ubuntu-22.04-node18
⚠️ [playwright-test] › ui-mode-test-watch.spec.ts:145:5 › should watch all @windows-latest-node18-1

37393 passed, 650 skipped
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Merge workflow run.