10.6 Fix tree node locator to work with umlauts correctly

[mugge6]

Tree node locator is comparing always the first and last child element with the current node to decide if the requested item was found on the current page. If there is a umlaut (äöü) on the key this doesn't work, because a simple comparison with < or > is based on their ASCI code. This fix will replace the comparison with the localeCompare function.

This fix should be contributed to Pimcore as soon as Cando will support one of the current versions from Pimcore.

[github-actions]

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• Target branch (11.0 for bug fixes, others 11.x)
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