Fix alt text

Author: v-regandowner

articles/aks/upgrade-cluster.md

@@ -153,7 +153,7 @@ To remove usage of deprecated APIs, follow these steps:
 
 1. Remove the deprecated API, which is listed in the error message. In the Azure portal, navigate to your cluster's overview page, and select **Diagnose and solve problems**. You can find recent usages detected under the **Known Issues, Availability and Performance** category by navigating to **Selected Kubernetes API deprecations** on the left-hand side. You can also check past API usage by enabling [container insights][container-insights] and exploring kube audit logs.
 
-    :::image type="content" source="./media/upgrade-cluster/applens-api-detection-inline.png" lightbox="./media/upgrade-cluster/applens-api-detection-full.png" alt-text="A screenshot of the Azure portal showing the 'Selected Kubernetes API deprecations' section ":::
+    :::image type="content" source="./media/upgrade-cluster/applens-api-detection-inline.png" lightbox="./media/upgrade-cluster/applens-api-detection-full.png" alt-text="A screenshot of the Azure portal showing the 'Selected Kubernetes API deprecations' section.":::
 
 2. Wait 12 hours from the time the last deprecated API usage was seen.