Add WebDriver BiDi network logging with stable request IDs

[juliandescottes]

• At least two implementers are interested (and none opposed):
  • Changes landed in WebDriver-BiDi with agreement in Browser Testing and Tools WG.
• Tests are written and can be reviewed and commented upon at:
  • https://wpt.fyi/results/webdriver/tests/bidi/network?label=experimental&label=master&aligned (there's no normative changes to fetch behaviour other than when WebDriver is enabled).
• Implementation bugs are filed:
  • Chromium: Network module GoogleChromeLabs/chromium-bidi#506
  • Gecko: https://bugzilla.mozilla.org/show_bug.cgi?id=1790366 (and similarly for other events)
• MDN issue is filed: …
  • No WebDriver BiDi documentation on MDN yet.
    (See WHATWG Working Mode: Changes for more details.)

This PR is based on the feedback on the existing PR #1540 as well as what was discussed in w3c/webdriver-bidi#722

This introduces the concept of a stable webdriver id for requests, which is consistent across redirects, authentication attempts and CORS preflight.

This also triggers steps from the webdriver bidi specification to emit network events and trigger data collection mecanisms.

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[juliandescottes]

@annevk hi! this PR is meant to take over #1540 which you initially reviewed. Could you take a look and let me know if this addresses the concerns you initially raised. Normally we clarified the expectations from WebDriver BiDi regarding the lifecycle of the request object in w3c/webdriver-bidi#722

[juliandescottes]

@annevk gentle ping - just updated the PR summary to use the expected template.

[juliandescottes]

@annevk @zcorpan it's been ~1month since the last activity on this PR, anything I can do to help it move forward?