Remove defunct splitview

[snowystinger]

Closes
Splitview is not a component we will be building. Design is finally settling and we'll have something that accomplishes similar goals, but will likely be by a different name with some different requirements. Rather than adapt this, we'll remove it for now to prevent confusion and when the new component comes along, we can look back to this if we need it.

✅ Pull Request Checklist:

• Included link to corresponding React Spectrum GitHub Issue.
• Added/updated unit tests and storybook for this change (for new code or code which already has tests).
• Filled out test instructions.
• Updated documentation (if it already exists for this component).
• Looked at the Accessibility Practices for this feature - Aria Practices

📝 Test Instructions:

🧢 Your Project:

[adobe-bot]

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[dannify]

So we might not have exported the actual component but for whatever reason it had types in react-types/shared which is a published package.
So can we actually remove those types or is that a breaking change?

[snowystinger]

@dannify great point, technically it would be breaking, though not sure who would be using them since we never released the hooks or component?
but maybe safer to leave them? lets get some other opinions

[adobe-bot]

Build successful! 🎉

• View the storybook
• View the storybook-17
• View the documentation

[dannify]

verbal approval from Devon 👍