Testing "invalid" `timeouts` configurations in `/webdriver/tests/classic/new_session/invalid_capabilities.py`

[trflynn89]

This test checks that the following timeouts configuration objects are rejected when creating a new session:

("timeouts", [
    1, [], "{}", False,
    {"invalid": 10},
    {"PAGELOAD": 10},
    {"page load": 10},
    {" pageLoad": 10},
    {"pageLoad ": 10},
    {"pageLoad": None},
    {"pageLoad": False},
    {"pageLoad": []},
    {"pageLoad": "10"},
    {"pageLoad": 2.5},
    {"pageLoad": -1},
    {"pageLoad": 2**53},
    {"pageLoad": {"value": 10}},
    {"pageLoad": 10, "invalid": 10},
]),

I had two questions about this data:

1. It seems that {"pageLoad": None} should not be rejected. The WebDriver spec now explicitly allows null timeout values. Is this right?
2. Should the presence of keys such as "invalid", "PAGELOAD", etc. actually be rejected? The timeouts deserialization steps explictly says to just ignore unknown keys. rather than returning an error:
   https://w3c.github.io/webdriver/#dfn-deserialize-as-timeouts-configuration

3. For each key → value in timeouts:
    1. If «"script", "pageLoad", "implicit"» does not contain key, then continue.

/webdriver/tests/classic/new_session/timeouts.py seems to have the same issue as (1) above, in that it is expecting null timeout values to be rejected

[Classicrichblog]

Implement for me