Detect file shares in storage account for use during setup process
When you are setting up Azure Cloud Shell, under the advanced options you have Create New/Use Existing options for the resource group, storage account, and file share. Use Existing works properly for the resource group and storage account, allowing users to choose an option from a list, and automatically setting the option if there is only one to choose from; however, for the file share option, if you select the Use Existing radio button nothing happens -- you don't get a list of shares to choose from, and if there is only one share, it is not automatically chosen. Please fix this so that use existing works properly for the file share selection as well.
