refining alt text

Author: v-dirichards

articles/aks/postgresql-ha-overview.md

@@ -51,7 +51,7 @@ This diagram illustrates a PostgreSQL cluster setup with one primary replica and
 
 Backups are stored on [Azure Blob Storage](/azure/storage/blobs/), providing another way to restore the database in the event of an issue with streaming replication from the primary replica.
 
-:::image source="./media/postgresql-ha-overview/architecture-diagram.png" alt-text="Screenshot showing CNPG architecture diagram." lightbox="./media/postgresql-ha-overview/architecture-diagram.png":::
+:::image source="./media/postgresql-ha-overview/architecture-diagram.png" alt-text="Diagram of CNPG architecture." lightbox="./media/postgresql-ha-overview/architecture-diagram.png":::
 
 > [!NOTE]
 > The CNPG operator supports only *one database per cluster*. Plan accordingly for applications that require data separation at the database level.