DEVX-657: fixing a bug in getLocalizedStringEntryCategoryMap

Author: ShipilA

commercetools/commercetools-sdk-java-api/src/main/java/com/commercetools/api/models/category/CategoryTreeFactory.java

@@ -68,7 +68,7 @@ private Map<LocalizedStringEntry, Category> getLocalizedStringEntryCategoryMap(
                     .collect(Collectors.toSet());
             localesForTheCategory.forEach(locale -> {
                 final LocalizedStringEntry stringsEntry = LocalizedStringEntry.of(locale,
-                    category.getSlug().values().get(locale));
+                    category.getSlug().get(locale));
                 categoriesByLocaleAndSlug.put(stringsEntry, category);
             });
         });