TreeNode hover styles only applied when hover is supported
#2618
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Changes
Fixes #2564, at least indirectly.
This PR follows the suggestion of adding hover styles only when hover is supported by the input mechanism.
Testing
Confirmed in the iPad simulator that the hover styles no longer show up in the sandbox from #2564.
Temporarily commented out the Tree hover test since it doesn't trigger the hover correctly, or something along those lines (#2618 (comment)). Added a TODO to investigate this later.
Docs
Added css and react patch changesets.