wdspec: Global Privacy Control is not part of spec

[yezhizhen]

I see #56495. It contains tests which uses command is not part of spec.

[yezhizhen]

cc @whimboo @jgraham @xiaochengh

[whimboo]

Maybe we should as best also add an external specifications section to the classic spec (similar to WebDriver BiDi) to reference those specifications that bring their own commands.

[gsnedders]

We kinda have two options here:

1. Add support for WebDriver tests in other directories (currently we only support WebDriver tests in /webdriver/ and /infrastructure/webdriver/),
2. Make it clearer that /webdriver/ contains all tests for WebDriver, regardless of what spec the endpoints are defined in, relying on subdirectories for other specs.

[whimboo]

Note that we have tests for permissions as well:
https://github.com/servo/servo/tree/main/tests/wpt/tests/webdriver/tests/classic/permissions

We should probably move them all under external/ similar to what we do for BiDi:
https://github.com/web-platform-tests/wpt/tree/master/webdriver/tests/bidi/external

[whimboo]

I opened #57268 to fix that issue by moving the tests into a sub folder and adding a README.md with details.

[whimboo]

#57268 was merged.