draft new idea for selector component

[britt6612]

What does this PR do?

Status: Early draft state for component/API feedback. Selection, accessibility, theming, keyboard logic has not been implemented.

Implemented the same storybook example as in Taylor PR

Introduces new set of "Selector" components:

• SelectorGroup
• Selector
• SelectorIndicator

Component	Styling responsibilities	State/behavior responsibilities	Configurable props
SelectorGroup	None	Manages selected state, passes down via context	--
Selector	none	We will use selected state from this component	--
SelectorIndicator	none	Renders selection indicator (RadioButton/CheckBox)

Considerations for how this was built

In this approach there are just 3 components:

• SelectorGroup (just a context provider but doesn’t enforce any layout)
• Selector (just a context consumer that passes selected state to its child render function and maybe Box container for proper accessibility role)
• SelectorIndicator (RadioButton/CheckBox)

Where should the reviewer start?

What testing has been done on this PR?

How should this be manually tested?

Do Jest tests follow these best practices?

• screen is used for querying.
• The correct query is used. (Refer to this list of queries)
• asFragment() is used for snapshot testing.

Any background context you want to provide?

What are the relevant issues?

Closes grommet/hpe-design-system#3840

Screenshots (if appropriate)

Do the grommet docs need to be updated?

Should this PR be mentioned in the release notes?

Is this change backwards compatible or is it a breaking change?

[britt6612]

Closing this PR as we've decided it doesn't warrant a Grommet component at this time.