Deprecate the Display Density Token in favour of `--ig-size` CSS variable

[simeonoff]

The currently exposed display density token for setting the size of various components should be deprecated in favour of the --ig-size CSS variable. The variable should be used to size various components. This will reduce prop drilling as well as simplify the styles by eventually removing any classes related to display density/size(i.e. --compact, --cosy).

This issue requires us to evaluate all components that currently use the display density token and remove class bindings based on the token. The --ig-size property should be used to control how components are sized, including other components internal to any parent component. This can be achieved by setting dimensions of various elements/components by using the sizable mixin or function where needed.

Affected components:

• Action Strip @simeonoff
• Banner @simeonoff
• Button @simeonoff
• Button Group @simeonoff
• Chip @simeonoff
• Input Group @simeonoff
• Select @simeonoff
• Combo + Simple Combo @simeonoff
• Date Picker + Date Range Picker @simeonoff
• Time Picker @simeonoff
• Dropdown @SisIvanova
• Grid (including children components) @simeonoff
• List @SisIvanova
• Paginator @SisIvanova
• Query Builder @SisIvanova
• Tree @SisIvanova