OXDEV-9553 Fix getting the last child in a template chain

Author: AshrafOxid

src/Resolver/TemplateChain/DataObject/TemplateChain.php

@@ -76,8 +76,20 @@ public function getParent(TemplateTypeInterface $templateType): TemplateTypeInte
 
     public function getLastChild(): TemplateTypeInterface
     {
-        reset($this->chain);
-        return current($this->chain);
+        $extendedNamespaces = [];
+        $lastChild = null;
+
+        foreach ($this->chain as $templateType) {
+            $parentNamespace = $templateType->getParentNamespace();
+            if ($parentNamespace) {
+                $extendedNamespaces[$parentNamespace] = true;
+            }
+            if (!isset($extendedNamespaces[$templateType->getNamespace()])) {
+                $lastChild = $templateType;
+            }
+        }
+
+        return $lastChild ?? reset($this->chain);
     }
 
     public function hasParent(TemplateTypeInterface $templateType): bool