fix: return empty dict if no customer results

enterprise_access/apps/api_client/lms_client.py

@@ -102,7 +102,7 @@ def get_enterprise_customer_data(self, enterprise_customer_uuid=None, enterprise
             payload = response.json()
             if results := payload.get('results'):
                 return results[0]
-            return payload
+            return {}
         except requests.exceptions.HTTPError as exc:
             logger.exception(exc)
             raise