Send invitation emails

ref #19

src/tests/test_api_exoscale.py

@@ -73,12 +73,8 @@ def test_successful_onboarding_new_organization(
     assert org.origin == exoscale_origin
     assert org.namespace.startswith("org-")
 
-    user = User.objects.get(email="test@example.com")
-    assert user.first_name == "Test"
-    assert user.last_name == "User"
     with scopes_disabled():
-        membership = org.memberships.get(user=user)
-        assert membership.role == "owner"
+        assert org.invitations.all().filter(email="test@example.com").exists()
 
     billing_entity = org.billing_entity
     assert billing_entity.name == "Test Organization Display (Exoscale)"
@@ -91,7 +87,10 @@ def test_successful_onboarding_new_organization(
 
     assert len(mail.outbox) == 2
     invitation_email = mail.outbox[0]
-    assert invitation_email.subject == "Welcome to Servala - Test Organization Display"
+    assert (
+        invitation_email.subject
+        == "You're invited to join Test Organization Display on Servala"
+    )
     assert "test@example.com" in invitation_email.to
 
     welcome_email = mail.outbox[1]