Make the user database the default instead of master

[BobDuffyIRL]

When conectint to a Fabric SQLDB in SSMS  its is very difficult as we need to also enter the datbase name 

(this is not so for any other SQL Edition)

We request that the default database for users be set the the Fabric SQLDB, so that they do not need to specify the database name in connections

It makes no sense to make master the defautl database if no one is allowed connect to it.

[akatesmith]

This is a change for SSMS, not for Fabric.