chore: Update TreeView API (#7613)
* chore: Update TreeView API
* fix docs
* fix dynamic example
* actually save
* fix docs
* review comments
* Revert change to not use hasChildItems
* add prop table
* fix docs example
* remove extra border attributes in theme
* fix snapshots
* fix: S2 treeview haschildnodes (#7694)
* fix logic to determine hasChildNodes
* revert breaking changes but use prop override
* match rac logic with hook
* Fix spacing regression
* fix chromatic merge
* fix lint
