Support Doctrine attributes alongside annotations in BaseTranslation (#44)

This PR adds Doctrine attributes to the MappedSuperclass
`BaseTranslation` while keeping the annotations in place. This allows
`BaseTranslation` to be used with either annotations or attribute-based
Doctrine configurations.

Author: relthyg

src/Entity/BaseTranslation.php

@@ -16,6 +16,7 @@
 /**
  * @ORM\MappedSuperclass
  */
+#[ORM\MappedSuperclass]
 class BaseTranslation
 {
     /**
@@ -25,6 +26,9 @@ class BaseTranslation
      *
      * @ORM\Column(type="integer")
      */
+    #[ORM\Id]
+    #[ORM\GeneratedValue]
+    #[ORM\Column(type: 'integer')]
     protected $id;
 
     /**
@@ -33,11 +37,13 @@ class BaseTranslation
      * @PolyglotAnnotation\Locale
      */
     #[Polyglot\Locale]
+    #[ORM\Column]
     protected $locale;
 
     /**
      * @ORM\JoinColumn(name="entity_id", referencedColumnName="id", nullable=false)
      */
+    #[ORM\JoinColumn(name: 'entity_id', referencedColumnName: 'id', nullable: false)]
     protected $entity;
 
     public function getLocale()