bug symfony#1475 [Turbo] add missing use statement (jrushlow)

This PR was merged into the 2.x branch.

Discussion
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[Turbo] add missing use statement

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| Issues        |
| License       | MIT

The new `Ux\...\ClassUtil` and the legacy `Doctrine\...\ClassUtils` are very similar. Adding the missing use statement with an alias to avoid IDE confusion :)

Commits
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6e5fe19 [Turbo] add missing use statement

src/Turbo/src/Doctrine/ClassUtil.php

@@ -11,6 +11,7 @@
 
 namespace Symfony\UX\Turbo\Doctrine;
 
+use Doctrine\Common\Util\ClassUtils as LegacyClassUtils;
 use Symfony\Component\VarExporter\LazyObjectInterface;
 
 /**
@@ -30,8 +31,8 @@ public static function getEntityClass(object $entity): string
         }
 
         // @legacy for old versions of Doctrine
-        if (class_exists(ClassUtils::class)) {
-            return ClassUtils::getClass($entity);
+        if (class_exists(LegacyClassUtils::class)) {
+            return LegacyClassUtils::getClass($entity);
         }
 
         return $entity::class;