TreeSelect selection expands sibling nodes above the selection

[dcbroad3]

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Current behavior
When a node is selected in the TreeSelect component, and the node is not at the root of the list of components, the component will expand any siblings of the node above it. This is because while iterating through children, it appends each sibling to the path as it iterates through instead of creating a new array with only the current iterating item added to the path.

Expected behavior
Only the selected node and its parents should be expanded.

[dcbroad3]

Any way I could get a review of this and the attached pull request? This still appears to be a bug in the latest version. We are working around this bug by using a wrapper component that overrides the method in question. The fix is just a one-line code change.