test(bidi): add missing snapshots for Firefox

[hbenl]

Fixes the following tests:

• tests/page/page-request-fulfill.spec.ts:
  • "should allow mocking binary responses"
  • "should allow mocking svg with charset"
• tests/library/screenshot.spec.ts:
  • "element screenshot should work with a mobile viewport"
  • "element screenshot should work with device scale factor"

[github-actions]

Test results for "tests 1"

1 failed
❌ [playwright-test] › reporter-html.spec.ts:1037 › merged › should have link for opening HTML attachments in new tab @macos-latest-node18-2

2 flaky

⚠️ [firefox-library] › library/inspector/cli-codegen-1.spec.ts:1079 › cli codegen › should not throw csp directive violation errors `@firefox-ubuntu-22.04-node18`
⚠️ [firefox-page] › page/page-event-request.spec.ts:182 › should return response body when Cross-Origin-Opener-Policy is set `@firefox-ubuntu-22.04-node18`

33896 passed, 636 skipped

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Merge workflow run.

[whimboo]

@hbenl, don't we also miss the firefox equivalent under tests/library/screenshot.spec.ts?

[hbenl]

@hbenl, don't we also miss the firefox equivalent under tests/library/screenshot.spec.ts?

Those tests are skipped for firefox.

[whimboo]

For the failing tests there was an issue with the blob-report, which is unrelated to this change.

@yury-s, can we please get this PR reviewed and merged?