chore(bidi): fix header overrides for redirects

[hbenl]

Fixes the following tests in page/page-request-continue.spec.ts:

• "should respect set-cookie in redirect response"
• "redirected requests should report overridden headers"
• "propagate headers cross origin redirect after interception"
• "should not forward Host header on cross-origin redirect"

[github-actions]

Test results for "MCP"

3 failed
❌ [chromium] › mcp/core.spec.ts:167 › browser_resize @mcp-macos-15
❌ [chromium] › mcp/launch.spec.ts:80 › persistent context @mcp-macos-15
❌ [chromium] › mcp/video.spec.ts:63 › should work with recordVideo (persistent) @mcp-macos-15

2819 passed, 116 skipped

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Merge workflow run.

[github-actions]

Test results for "tests 1"

6 failed
❌ [default-trace] › debug-tests.spec.ts:516 › should not pause at the end of a setup test @vscode-extension
❌ [playwright-test] › expect.spec.ts:697 › should not print timed out error message when test times out @macos-latest-node20
❌ [playwright-test] › expect.spec.ts:716 › should not leak long expect message strings @macos-latest-node20
❌ [playwright-test] › expect.spec.ts:834 › should chain expect matchers and expose matcher utils @macos-latest-node20
❌ [playwright-test] › playwright.spec.ts:485 › should work with video: on-first-retry @macos-latest-node20
❌ [playwright-test] › playwright.spec.ts:877 › page.pause() should disable test timeout @macos-latest-node20

6 flaky

⚠️ [chromium-library] › library/popup.spec.ts:258 › should not throw when click closes popup `@ubuntu-22.04-chromium-tip-of-tree`
⚠️ [chromium-library] › library/inspector/cli-codegen-pick-locator.spec.ts:35 › should update locator highlight `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-page] › page/page-request-continue.spec.ts:754 › propagate headers cross origin redirect after interception `@chromium-ubuntu-22.04-node24`
⚠️ [chromium-library] › library/popup.spec.ts:258 › should not throw when click closes popup `@chromium-ubuntu-22.04-node22`
⚠️ [playwright-test] › runner.spec.ts:124 › should ignore subprocess creation error because of SIGINT `@macos-latest-node20`
⚠️ [playwright-test] › ui-mode-trace.spec.ts:379 › should reveal errors in the sourcetab `@windows-latest-node20`

34445 passed, 696 skipped

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Merge workflow run.