test(bidi): always install chromium in CI

[hbenl]

The trace-viewer tests are still failing for Firefox in CI because they need Chromium to be installed.

[github-actions]

Test results for "tests 1"

1 failed
❌ [playwright-test] › expect.spec.ts:642 › should only highlight unmatched regex in diff message for toHaveText with array @macos-latest-node20

3 flaky

⚠️ [chromium-library] › library/popup.spec.ts:258 › should not throw when click closes popup `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/popup.spec.ts:258 › should not throw when click closes popup `@chromium-ubuntu-22.04-node20`
⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:1082 › cli codegen › should not throw csp directive violation errors `@firefox-ubuntu-22.04-node20`

38485 passed, 839 skipped

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Merge workflow run.

[github-actions]

Test results for "MCP"

3 failed
❌ [chrome] › mcp/autowait.spec.ts:19 › racy navigation destroys context @mcp-windows-latest
❌ [chrome] › mcp/roots.spec.ts:47 › check that trace is saved in workspace @mcp-windows-latest
❌ [msedge] › mcp/roots.spec.ts:47 › check that trace is saved in workspace @mcp-windows-latest

4802 passed, 135 skipped

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Merge workflow run.