Create smaller variations for form elements

Several places in Claro use the regular size for input fields and take a lot of vertical space.

As we have for buttons, we need smaller and more compact input and selects for smaller forms like the content page filter or the people page filter.

~~Create design~~s
~~Create specs~~
Create styles for smaller inputs/selects.
It should be possible to target a single element by adding a class to that element
It should also be possible to target all elements within a form by adding a single class to the form. Although button variants already exist, button CSS will need updating to allow variant-styling based on a parent class such as .form--small
Implement it on views filters and textarea formatting select.

Some forms will result on taking less space.

Small size:
- Filters for the following lists:
/admin/content
/admin/people
Extra Small size:
Textarea formatting select
node/add/page