PowerBI connecting to Azure SQL DB without username and Password.

I am tryuing to get rid of username and password from Azure SQL DB.
PowerBI is using username and password to connect to this DB, I am trying to move away from username Password based authentication.
What are other ways by which I can connect to Azure SQL DB which doesn't allow All Azure Services but a specific VNET and some IP's in the firewall rule.
I am following the below doc for migration and support of PpowerBI to SQL buit can't find a way on how to connect.
Securing the connection between Power BI and Azure SQL Database | Microsoft Azure Blog