Fix Issue 7409 (az storage cors list missing "Service" field)

[earthquakesan]

This PR fixes the issue #7409 #7409.

Steps to reproduce the issue:

1. Set AZURE_STORAGE_ACCOUNT and AZURE_STORAGE_KEY variables (refer to the documentation if necessary: https://docs.microsoft.com/en-us/azure/storage/blobs/storage-quickstart-blobs-cli)

2. Add 2 or more CORS rules of same type (here are file rules from original issue).

#!/bin/bash

az storage cors clear --services f

az storage cors add \
	--allowed-headers "x-api-key" \
       	--methods GET \
       	--origins http://localhost:5000 \
       	--exposed-headers "x-ms-request-id, x-ms-lease-status" \
       	--max-age 10 \
       	--services f

az storage cors add \
	--allowed-headers "content-type" \
       	--methods GET \
       	--origins http://localhost:5001 \
       	--exposed-headers "x-*" \
       	--max-age 5 \
       	--services f

az storage cors add \
	--allowed-headers "x-api-key, x-app-*" \
       	--methods POST \
       	--origins http://localhost:5000 http://localhost:5001 \
       	--exposed-headers "*" \
       	--max-age 5 \
       	--services f

az storage cors add \
	--allowed-headers "*" \
       	--methods GET \
       	--origins "*" \
       	--exposed-headers "*" \
       	--max-age 30 \
       	--services f

1. Execute az storage cors list

Example Output

[
  {
    "AllowedHeaders": "x-api-key",
    "AllowedMethods": "GET",
    "AllowedOrigins": "http://localhost:5000",
    "ExposedHeaders": "x-ms-request-id, x-ms-lease-status",
    "MaxAgeInSeconds": 10,
    "Rule": 1,
    "Service": "file"
  },
  {
    "AllowedHeaders": "content-type",
    "AllowedMethods": "GET",
    "AllowedOrigins": "http://localhost:5001",
    "ExposedHeaders": "x-*",
    "MaxAgeInSeconds": 5,
    "Rule": 2,
    "Service": ""
  },
  {
    "AllowedHeaders": "x-api-key, x-app-*",
    "AllowedMethods": "POST",
    "AllowedOrigins": "http://localhost:5000, http://localhost:5001",
    "ExposedHeaders": "*",
    "MaxAgeInSeconds": 5,
    "Rule": 3,
    "Service": ""
  },
  {
    "AllowedHeaders": "*",
    "AllowedMethods": "GET",
    "AllowedOrigins": "*",
    "ExposedHeaders": "*",
    "MaxAgeInSeconds": 30,
    "Rule": 4,
    "Service": ""
  }
]

Expected Output

[
  {
    "AllowedHeaders": "x-api-key",
    "AllowedMethods": "GET",
    "AllowedOrigins": "http://localhost:5000",
    "ExposedHeaders": "x-ms-request-id, x-ms-lease-status",
    "MaxAgeInSeconds": 10,
    "Rule": 1,
    "Service": "file"
  },
  {
    "AllowedHeaders": "content-type",
    "AllowedMethods": "GET",
    "AllowedOrigins": "http://localhost:5001",
    "ExposedHeaders": "x-*",
    "MaxAgeInSeconds": 5,
    "Rule": 2,
    "Service": "file"
  },
  {
    "AllowedHeaders": "x-api-key, x-app-*",
    "AllowedMethods": "POST",
    "AllowedOrigins": "http://localhost:5000, http://localhost:5001",
    "ExposedHeaders": "*",
    "MaxAgeInSeconds": 5,
    "Rule": 3,
    "Service": "file"
  },
  {
    "AllowedHeaders": "*",
    "AllowedMethods": "GET",
    "AllowedOrigins": "*",
    "ExposedHeaders": "*",
    "MaxAgeInSeconds": 30,
    "Rule": 4,
    "Service": "file"
  }
]

Comments

The problem was in the formatter function, which reset "Service" key output for each item except for the first one. I also removed unnecessary service_name variable

Checklists

• The PR has modified HISTORY.rst describing any customer-facing, functional changes. Note that this does not include changes only to help content. (see Modifying change log).

This PR does not change or add any functionality, bugfix only.

• I adhere to the Command Guidelines.

This PR does not change or add any functionality, bugfix only.

[msftclas]

All CLA requirements met.

[troydai]

Thank you very much @earthquakesan . Looks good to me. @williexu can you come up with additional tests to cover this scenario?

Remove myself from the reviewers as I'm leaving the project.

[williexu]

LGTM, I'll merge this and add some additional testing.