- swap margins to gap instead

- now entirely handled by `EuiFormControlLayout`

+ remove ignored `icon` prop being passed to EuiFieldText, does nothing if `controlOnly` is passed

- not really worth avoiding the nesting here

- Allows us to remove `margin`s from `EuiHue`
- Allows us to remove a bunch of conditional `EuiSpacer`s that didn't account  for every possible permutation

+ remove extra `<div>` wrapper in favor of passing `onKeyDown` events directly to child `EuiHue` and `EuiSaturation`

- tweak `EuiHue` to have a single wrapper (to work with flex gap) instead of multiple top level children. DOM shouldn't impact a11y behavior

+ fix incorrect `compressed` behavior on secondary input display, compressed is always true for that (vs the popover form control)

- remove unnecessary vars and just inline them since they only have 1 usage

- remove `.euiColorPicker__swatch-item` - not used anywhere in either EUI or Kibana

- remove `.euiColorPicker__swatchSelect` - not used in Kibana and can be replaced with component className instead in EUI

- convert Enzyme to RTL

- add `shouldRenderCustomStyles`

- update snapshots

- make it so user input changes the input (easier to QA/test) and also add an onChange action

- allow color/format controls to update the story correctly as expected

- show secondary input automatically if `mode` is set that way

- remove double form control layout wrapper
- fix clear icon not correctly stacking with invalid icon (needs to be passed to form control layout)

- allow compressed state of input to be controlled when `display` is inline, otherwise default to compressed