fix(combobox): onValueChange was triggered even when selected item ha…

[Powerplex]

Description, Motivation and Context

In the singleSelectionReducer, when blur event is triggered or disclosureButton is clicked, it calls setSelectedItem to reset it, which in return triggers onValueChange prop (callback).

I added an optimization to check that the selected item (or none item selected) has changed before triggering the callback, which was called too many times.

Types of changes

• [x] 🪲 Bug fix (non-breaking change which fixes an issue)

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 97.63%. Comparing base (917e9ce) to head (30d9012). Report is 8 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2187 +/- ## ======================================= Coverage 97.63% 97.63% ======================================= Files 749 749 Lines 5880 5885 +5 Branches 2074 2076 +2 ======================================= + Hits 5741 5746 +5 Misses 137 137 Partials 2 2 ```

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