🐛(backend) update alter file state migration predecessor

Last PR was merged a bit too quicly and another migration
was added before the PR one.

src/backend/core/migrations/0020_alter_file_upload_state.py

@@ -1,4 +1,4 @@
-# Generated by Django 5.2.14 on 2026-06-02 12:47
+# Generated by Django 5.2.14 on 2026-06-03 12:14
 
 from django.db import migrations, models
 
@@ -6,7 +6,7 @@ from django.db import migrations, models
 class Migration(migrations.Migration):
 
     dependencies = [
-        ('core', '0018_rename_active_application_is_active'),
+        ('core', '0019_user_unique_email_when_sub_is_null'),
     ]
 
     operations = [