Fix typo

Websocket -> WebSocket

Author: changeworld

articles/api-management/graphql-api.md

@@ -128,7 +128,7 @@ If your GraphQL  API supports a subscription, you can test it in the test consol
     :::image type="content" source="media/graphql-api/test-graphql-subscription.png" alt-text="Screenshot of a subscription query in the query editor.":::
 1. Review connection details in the **Subscription** pane. 
 
-    :::image type="content" source="media/graphql-api/graphql-websocket-connection.png" alt-text="Screenshot of Websocket connection in the portal.":::
+    :::image type="content" source="media/graphql-api/graphql-websocket-connection.png" alt-text="Screenshot of WebSocket connection in the portal.":::
 
 1. Subscribed events appear in the **Subscription** pane. The WebSocket connection is maintained until you disconnect it or you connect to a new WebSocket subscription.