[ARM] Az Deployments : Add support for --query-string

[detienne20]

PR is dependent on #16179.

Description

Az deployments now supports --query-string to be used with --template-uri for linked template deployments; --query-string is a SAS token for a storage container that contains the main template and linked template(s). Support for the --query-string parameter will facilitate the transition to template specs. Like with template specs linked templates are referenced through the relative path field in template link as illustrated below:

    "templateLink":  {
              "relativePath":"linked_template.json",
               "contentVersion":"1.0.0.0"
     }

Testing Guide

1. Create storage account container and upload files for deployment.

   az storage account create -n {} -g {} -l {} --sku {} --kind {}
   az storage container create -n {} --account-name {}
   az storage blob upload -c {} -f "{}" -n {} --account-name {}

2. Generate an SAS token for the entire container (query-string parameter)

   az storage container generate-sas --account-name {} --account-key {} --name {} --permissions dlrw --expiry {}

3. Generate the url for the main template (template-uri parameter)

   az storage blob url -c {} -n {} --account-name {}

4. Deploy with --template-uri and --query-string parameter.

   az deployment group create -g {} --template-uri {blob_url} --query-string "{sas_token}"
   az deployment sub create -g {} --template-uri {blob_url} --query-string "{sas_token}"
   az deployment mg validate -g {} --template-uri {blob_url} --query-string "{sas_token}"
   az deployment tenant validate -g {} --template-uri {blob_url} --query-string "{sas_token}"

[yonzhan]

ARM

[detienne20]

Created new PR #16447 without extra reviewers/changes.