Migration: Fix missing "on delete" in new gradebook_category.document_id FK

src/CoreBundle/Migrations/Schema/V200/Version20230405123419.php

@@ -23,7 +23,7 @@ final class Version20230405123419 extends AbstractMigrationChamilo
         }
         if ($schema->hasTable('gradebook_category')) {
             $this->addSql(
-                'ALTER TABLE gradebook_category ADD CONSTRAINT FK_96A4C705C33F7837 FOREIGN KEY (document_id) REFERENCES c_document (iid);'
+                'ALTER TABLE gradebook_category ADD CONSTRAINT FK_96A4C705C33F7837 FOREIGN KEY (document_id) REFERENCES c_document (iid) ON DELETE SET NULL;'
             );
             $this->addSql(
                 'CREATE UNIQUE INDEX UNIQ_96A4C705C33F7837 ON gradebook_category (document_id);'