Remove the "scheduled_for_deletion" field from the StockItem model

Reverts back to the original behaviour - stock items are just deleted

InvenTree/stock/migrations/0072_remove_stockitem_scheduled_for_deletion.py

@@ -0,0 +1,17 @@
+# Generated by Django 3.2.5 on 2021-12-05 06:49
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0071_auto_20211205_1733'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='stockitem',
+            name='scheduled_for_deletion',
+        ),
+    ]