Add ability to download browsers (not just drivers) with the `sbase get` command

[mdmintz]

Add ability to download browsers (not just drivers) with the sbase get command.

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Browser Binaries:

🎛️ Use the sbase get command to download the Chrome for Testing and Chrome-Headless-Shell browser binaries. Example:

sbase get cft  # (For `Chrome for Testing`)
sbase get chs  # (For `Chrome-Headless-Shell`)

Those commands download those binaries into the seleniumbase/drivers folder.
To use the binaries from there in SeleniumBase scripts, set the binary_location to cft or chs.

See https://googlechromelabs.github.io/chrome-for-testing/ for info about Chrome for Testing and Chrome-Headless-Shell.

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Setting the binary location:

🔵 By default, SeleniumBase uses the browser binary detected on the System PATH.

🎛️ To change this default behavior, you can use:

pytest --binary-location=PATH

The PATH in --binary-location=PATH / --bl=PATH can be:

• A relative or exact path to the browser binary.
• "cft" as a special option for Chrome for Testing.
• "chs" as a special option for Chrome-Headless-Shell.

Before using the "cft" / "chs" options, call sbase get cft / sbase get chs in order to download the specified binaries into the seleniumbase/drivers folder. The default version is the latest stable version on https://googlechromelabs.github.io/chrome-for-testing/. You can change that by specifying the arg as a parameter. (Eg. sbase get cft 131, sbase get chs 132, etc.)

With the SB() and Driver() formats, the binary location is set via the binary_location parameter.

[mdmintz]

This was resolved in 4.34.2 - https://github.com/seleniumbase/SeleniumBase/releases/tag/v4.34.2