PostCSS Logical not transpiling flow relative properties (e.g. float: inline-start) which are not supported by Chrome and Safari

In #3312481: Update core's browserlist we updated the browserlist database which determines what CSS properties PostCSS will transpile. With this update, Drupal core is not transpiling any logical properties.

However, there are certain properties which our supported browsers do not support, including flow relative properties such as `float: inline-end`, and `clear: inline-start`. You can see current browser support for these properties at https://caniuse.com/mdn-css_properties_clear_flow_relative_values.

The Chromium issue to implement this is at https://bugs.chromium.org/p/chromium/issues/detail?id=850004. I can’t find the webkit issue.

I created an upstream bug for PostCSS Logical at https://github.com/csstools/postcss-plugins/issues/632

Edit after the fact

This will likely never be fixed within PostCSS. I created an issue upstream at https://github.com/csstools/postcss-plugins/issues/958, where I discovered that PostCSS Logical doesn't compile to both RTL and LTR anymore. You have to pick one or the other (this is new to version 8 of PostCSS Logical). This doesn't affect Drupal except within the float and clear properties. We'll have to manually add the dir attributes when using those.

Task

It'd be nice if either 1) this could be fixed upstream or 2) we could set PostCSS Logical to always transpile these values. But, for now, I think we need to change the float values to use non-logical CSS properties. This should be an easy task, as they're only used in a few places within Olivero.