If specifying an invalid `by`, fail fast, rather than after trying to find an element

[mdmintz]

If specifying an invalid by, fail fast, rather than after trying to find an element

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These are the valid by options: "css selector", "link text", "partial link text", "name", "xpath", "id", "tag name", and "class name".

By default, SeleniumBase autodetects between "css selector" and "xpath" if the by is not specified.

If people try to specify an invalid by, it should raise an exception right away. (Currently, it tries waiting for the element up to the timeout, and that would eventually fail.)

[mdmintz]

This was resolved in 4.29.7 - https://github.com/seleniumbase/SeleniumBase/releases/tag/v4.29.7