[docs][Slider] Outdated guidance for vertical sliders

[mj12albert]

Follow up to mui/base-ui#635

Related page

https://mui.com/material-ui/react-slider/#vertical-sliders

1. Current docs recommend -webkit-appearance: slider-vertical, which will cause a console warning in Chrome 124+.
2. The browser bug where -webkit-appearance: slider-vertical reverses arrow key behavior has been fixed in Jan 2021: https://issues.chromium.org/issues/40739626#comment9 Our lowest supported chrome version is 109 which was released in 2023

[mj12albert]

I suggest we do:

1. Update the content about the reversed arrow keys, it's outdated and the underlying issue in Chromium has been fixed
2. Update the content about -webkit-appearance: slider-vertical, it's only relevant to Chrome <124 now
3. Add CSS writing-mode to the built-in styles, this is a simple fix to expose the component correctly in the accessibility tree we can do right now, no need to wait for Base UI

Sandbox comparing -webkit-appearance: slider-vertical vs writing-mode: https://codesandbox.io/p/sandbox/xhmkxy

[mj12albert]

@oliviertassinari @aarongarciah I think we can make a worthwhile improvement here right now, regardless of the status/timing of integrating Base UI, what do you think?

[aarongarciah]

@mj12albert +1