Update ADF tests to latest resource manager client

[bgold09]

Description

Update ADF tests to latest resource manager client

• Tests now use Microsoft.Azure.Management.ResourceManager version
  1.6.0-preview
• Modify all tests to create and delete a resource group
• resolves Re-record test using latest resource manager #3726

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[bgold09]

@shahabhijeet please take a look when you can 😄