Set up clients wrapper to hold all the clients

- tests FAIL if there is a provider in the DB and not in the CODE
- tests PASS is there a provider in the CODE and not in the DB

tests/app/dao/test_provider_details.py

@@ -0,0 +1,24 @@
+from app.models import ProviderDetails
+from app import clients
+
+
+def test_should_error_if_any_provider_in_database_not_in_code(notify_db, notify_db_session, notify_api):
+    providers = ProviderDetails.query.all()
+
+    for provider in providers:
+        if provider.notification_type == 'sms':
+            assert clients.sms_client(provider.identifier)
+        if provider.notification_type == 'email':
+            assert clients.email_client(provider.identifier)
+
+
+def test_should_not_error_if_any_provider_in_code_not_in_database(notify_db, notify_db_session, notify_api):
+    providers = ProviderDetails.query.all()
+
+    ProviderDetails.query.filter_by(identifier='mmg').delete()
+
+    for provider in providers:
+        if provider.notification_type == 'sms':
+            assert clients.sms_client(provider.identifier)
+        if provider.notification_type == 'email':
+            assert clients.email_client(provider.identifier)