Add FOR JSON support in fabric warehouse

The FOR JSON syntax in T-SQL is a powerful way to create json objects from select statements. This can be useful both to export data but also to pass parameters to for example Data factory if working with a metadata driven framework.

As this functionality is working in most Microsoft SQL offerings including Serverless SQL pools in Synapse, and I know a lot of organizations have built features around it. It would be great to add this functionality in Fabric Data Warehouse as well.