Revise note on database snapshots overhead

Updated note regarding CPU and IO overhead when creating database snapshots.

Author: MikeyBronowski

docs/database-engine/availability-groups/windows/database-snapshots-with-always-on-availability-groups-sql-server.md

@@ -15,7 +15,8 @@ helpviewer_keywords:
 # Database Snapshots with Always On Availability Groups (SQL Server)
 [!INCLUDE [SQL Server](../../../includes/applies-to-version/sqlserver.md)]
 
-[!NOTE] Creating database snapshots on any database has cpu and IO overhead due to copy on write activity. On database replicas, this can hurt redo throughput among other operations, especially as the number of snapshots increases.
+> [!NOTE]
+> Creating database snapshots on any database has cpu and IO overhead due to copy on write activity. On database replicas, this can hurt redo throughput among other operations, especially as the number of snapshots increases.
 
   You can create a database snapshot on an primary or secondary database in an availability group. The replica role must be either PRIMARY or SECONDARY, not in the RESOLVING state.