minor #18318 [Doctrine] Add missing use statement to databases & doctrine page (jontjs)

This PR was merged into the 6.2 branch.

Discussion
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[Doctrine] Add missing `use` statement to databases & doctrine page

The example at https://symfony.com/doc/current/doctrine.html#updating-an-object is missing a `use` statement.

Commits
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ae34e2c Add missing `use` statement to databases & doctrine page

Author: javiereguiluz

doctrine.rst

@@ -813,6 +813,7 @@ with any PHP model::
 
     use App\Entity\Product;
     use App\Repository\ProductRepository;
+    use Doctrine\ORM\EntityManagerInterface;
     use Symfony\Component\HttpFoundation\Response;
     use Symfony\Component\Routing\Annotation\Route;
     // ...