feat(Tree): expand all siblings on asterisk key

[silviuaavram]

Follows the pattern at https://www.w3.org/TR/wai-aria-practices-1.1/examples/treeview/treeview-1/treeview-1a.html in the keyboard support 'asterisk' section.

On asterisk key, the tree and all its siblings are expanded.

[codecov]

Codecov Report

Merging #1457 into master will increase coverage by 0.33%.
The diff coverage is 88.23%.

@@            Coverage Diff             @@
##           master    #1457      +/-   ##
==========================================
+ Coverage   73.14%   73.47%   +0.33%     
==========================================
  Files         805      806       +1     
  Lines        6073     6089      +16     
  Branches     1794     1780      -14     
==========================================
+ Hits         4442     4474      +32     
+ Misses       1625     1609      -16     
  Partials        6        6

Impacted Files	Coverage Δ
...ages/react/test/specs/behaviors/testDefinitions.ts	98.3% <ø> (ø)	⬆️
packages/react/src/components/Tree/TreeItem.tsx	80% <ø> (+73.33%)	⬆️
...c/lib/accessibility/Behaviors/Tree/treeBehavior.ts	100% <100%> (ø)	⬆️
...ib/accessibility/Behaviors/Tree/subtreeBehavior.ts	100% <100%> (ø)
packages/react/src/components/Tree/Tree.tsx	71.42% <84.61%> (+16.25%)	⬆️
packages/react/src/components/Tree/TreeTitle.tsx	50% <0%> (+40%)	⬆️

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