StorageAccountConfig.Key should return the key but returns full connection string

[mgrzyb]

From the source code:

type StorageAccountConfig = { 
... 
} with

    /// Gets the ARM expression path to the key of this storage account.
    member this.Key = StorageAccount.getConnectionString (this.Name)

Maybe this one should be obsoleted, a new property AccountKey exposed returning just the key, and connection string can either be acquired by using StorageAccount.getConnectionString or another property ConnectionString is added.