Support dynamic sources and destinations in Dataflow Gen2

[miguel]

With the introduction of public parameters in Dataflow Gen2,  you are now able to modify the arguments passed to a data source function (such as the server and database name for the Sql.Database function).

However, when you pass a value that alters the values that were originally defined for the Dataflow, to create its resource path), the Dataflow throws a credential challenge error because the connection that was linked / bound to the Dataflow is specific to the originally set resource path.

This idea is a request to enable dynamic connections so that an user can use the same set of credentials (or token) to refresh a Dataflow regardless of how the resource path was changed after passing values through the public parameteres of Dataflow Gen2.