Make the Data Reference a little nicer (#11262)

* font size, card around content

* table detail page styling

* clean up see-this-table button

* field detail styling

* improve field lists

* tighten up spacing

* fix up field list spacing

* sidebar styling

* field list spacing, page header icons

* clean up segment detail pages

* metric detail styling

* clean up lists

* list item sizing

* more spacing

* remove viewbox insanity

* add field descriptions to metric group-bys

* fix segments based-on link

* fix item list icon spacing

* fix edit header bg color

* lint picking

* prettier

* update e2e test

* try fixing e2e test again

* fix up e2e test selectors

* address kdoh's feedback