* fix accelerator behavior for menu items and labels
* add elements with matching accelerator to test cycling in sub menus
* Add AccessKeyHandler tests for accelerators with more than one match
* Implement accelerator behavior based on WPF handling
* Remove commented code
* Remove OnAccessKey override => handled by DefaultMenuInteractionHandler
* remove obsolete test
* handle OnAccessKeyPressed for selected tab item
* fix unit tests
* use AccessKeyEvent instead of AccessKeyPressedEvent in unit tests
* navigate menu with and without ALT key
* Revert formatting changes in Tests
* Fix AccessKeyHandler comments
* move private types to bottom
* Remove lock statements, optimize removal of AccessKeyRegistrations
* remove call to Dispatcher.UIThread.Post
* simplifiy AccessKeyHandler.SortByHierarchy
* remove unnecessary method AccessKeyHandler.GetTargetsForSender
* regenerate API suppression file
* revert unneeded changes in MenuPage.axaml
* correct formatting changes
* do not sort by hierarchy if too few targets
* make AccessKeyEventArgs internal
* make AccessKeyPressedEventArgs internal
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Co-authored-by: Hans Docsek <hans.docsek@gmail.com>
StefanKoell