The SUPER privilege is not supported on Azure Database for MySQL. The closest you can get is to create another admin level user with the same rights as the server admin you created to do this you can run:
CREATE USER 'testuser'@'%' IDENIFIED BY 'your_password_here';
GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, RELOAD, PROCESS, REFERENCES, INDEX, ALTER, SHOW DATABASES, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE, REPLICATION SLAVE, REPLICATION CLIENT, CREATE VIEW, SHOW VIEW, CREATE ROUTINE, ALTER ROUTINE, CREATE USER, EVENT, TRIGGER ON *.* TO 'testuser'@'%' WITH GRANT OPTION;
You can get the privileges the admin account has by logging in as the admin account and running:
SHOW GRANTS FOR CURRENT_USER;
This does mean you cannot run things like SET GLOBAL, to set global level settings please use the properties items in the portal.