Adds 'quarantine' code for StockItemStatus (#3084)

* Adds 'quarantine' code for StockItemStatus

- Marks item as "unavailable"
- Removes unused code from StockItemStatus class

* Add migration file

InvenTree/stock/migrations/0076_alter_stockitem_status.py

@@ -0,0 +1,19 @@
+# Generated by Django 3.2.13 on 2022-05-27 04:40
+
+import django.core.validators
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('stock', '0075_auto_20220515_1440'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='stockitem',
+            name='status',
+            field=models.PositiveIntegerField(choices=[(10, 'OK'), (50, 'Attention needed'), (55, 'Damaged'), (60, 'Destroyed'), (70, 'Lost'), (65, 'Rejected'), (75, 'Quarantined'), (85, 'Returned')], default=10, validators=[django.core.validators.MinValueValidator(0)]),
+        ),
+    ]