Add cron job for removing expired stored objects

Introduced `RemoveExpiredStoredObjectCronJob` to automate the deletion of expired stored objects every 7 days. Enhanced associated tests and updated relevant interfaces and classes to support the new cron job functionality.

src/Bundle/ChillDocStoreBundle/Service/StoredObjectManagerInterface.php

@@ -39,7 +39,9 @@ interface StoredObjectManagerInterface
     public function read(StoredObject|StoredObjectVersion $document): string;
 
     /**
-     * Set the content of a StoredObject.
+     * Register the content of a new version for the StoredObject.
+     *
+     * The manager is also responsible for registering a version in the StoredObject, and return this version.
      *
      * @param StoredObject $document     the document
      * @param string       $clearContent The content to store in clear
@@ -52,6 +54,11 @@ interface StoredObjectManagerInterface
     public function write(StoredObject $document, string $clearContent, ?string $contentType = null): StoredObjectVersion;
 
     /**
+     * Remove a version from the storage.
+     *
+     * This method is also responsible for removing the version from the StoredObject (using @see{StoredObject::removeVersion})
+     * in case of success.
+     *
      * @throws StoredObjectManagerException
      */
     public function delete(StoredObjectVersion $storedObjectVersion): void;