Simpify org types migration script and introduce foreign key

Don't transform org types on prod

tests/app/service/test_rest.py

@@ -574,7 +574,7 @@ def test_update_service(client, notify_db, sample_service):
         'email_from': 'updated.service.name',
         'created_by': str(sample_service.created_by.id),
         'email_branding': str(brand.id),
-        'organisation_type': 'foo',
+        'organisation_type': 'school_or_college',
     }
 
     auth_header = create_authorization_header()
@@ -589,7 +589,25 @@ def test_update_service(client, notify_db, sample_service):
     assert result['data']['name'] == 'updated service name'
     assert result['data']['email_from'] == 'updated.service.name'
     assert result['data']['email_branding'] == str(brand.id)
-    assert result['data']['organisation_type'] == 'foo'
+    assert result['data']['organisation_type'] == 'school_or_college'
+
+
+def test_cant_update_service_org_type_to_random_value(client, sample_service):
+    data = {
+        'name': 'updated service name',
+        'email_from': 'updated.service.name',
+        'created_by': str(sample_service.created_by.id),
+        'organisation_type': 'foo',
+    }
+
+    auth_header = create_authorization_header()
+
+    resp = client.post(
+        '/service/{}'.format(sample_service.id),
+        data=json.dumps(data),
+        headers=[('Content-Type', 'application/json'), auth_header]
+    )
+    assert resp.status_code == 500
 
 
 def test_update_service_letter_branding(client, notify_db, sample_service):

tests/conftest.py

@@ -102,6 +102,7 @@ def notify_db_session(notify_db):
                             "provider_details_history",
                             "template_process_type",
                             "notification_status_types",
+                            "organisation_types",
                             "service_permission_types",
                             "auth_type",
                             "invite_status_type",