use user delegation key to get blobs

[sahuroshan]

The current way of getting backup files from storage account was failing if we disable shared key access in storage account . With recent security push we need to disable shared key access for storage accounts. This PR contains the change for using user delegation key to get the backup files , user delegation key method works even if the shared key access is disabled for storage accounts.

ADO task - https://msdata.visualstudio.com/Database%20Systems/_workitems/edit/31210535

Reference code - https://github.com/Azure-Samples/AzureStorageSnippets/blob/master/blobs/howto/JavaScript/NodeJS-v12/dev-guide/list-blobs-from-container-sas-token.js

https://learn.microsoft.com/en-us/azure/storage/common/shared-key-authorization-prevent?tabs=portal#understand-how-disallowing-shared-key-affects-sas-tokens

https://learn.microsoft.com/en-us/azure/storage/common/storage-sas-overview

[kburtram]

@sahuroshan are you still working on this PR or should we close it out as abandoned?

[sahuroshan]

@sahuroshan are you still working on this PR or should we close it out as abandoned?

Hi @kburtram , This was paused because of security push , we will be starting again on this soon.