Issue 50507 - Fix Cockpit UI styling for PF4
Description: Fix the UI stylings to be aligned with Patternfly 4.
Also cleaned up ds.css to remove unused and duplicate
classes.
Added framework for PF React 4 so we start porting
PF React to version 4 as well.
relates: https://pagure.io/389-ds-base/issue/50507
Reviewed by: spichugi(Thanks!)