Test case AzureRMProfileTests.LoadingProfileWorks randomly failed

Observed at least twice for this test case's failure, one time is on Windows and one time is on Linux.

CI: https://dev.azure.com/azure-sdk/public/_build/results?buildId=262777&view=results

Attached log:
[VssAdministrator_fv-az639_2020-02-17_08_13_19.log](https://github.com/Azure/azure-powershell/files/4217480/VssAdministrator_fv-az639_2020-02-17_08_13_19.log)

Detail log info:

[xUnit.net 00:00:11.55] Microsoft.Azure.Commands.ResourceManager.Common.Test.AzureRMProfileTests.LoadingProfileWorks [FAIL]
X Microsoft.Azure.Commands.ResourceManager.Common.Test.AzureRMProfileTests.LoadingProfileWorks [26ms]
EXEC : error Message: [D:\a\1\s\build.proj]
Assert.Null() Failure
Expected: (null)
Actual: Byte[] [2, 0, 0, 0, 0, ...]
Stack Trace:
at Microsoft.Azure.Commands.ResourceManager.Common.Test.AzureRMProfileTests.LoadingProfileWorks() in D:\a\1\s\src\Accounts\Accounts.Test\AzureRMProfileTests.cs:line 1016
Results File: D:\a\1\s\artifacts\TestResults\VssAdministrator_fv-az639_2020-02-17_08_13_19.trx

Start with src/Accounts/Accounts.Test/AzureRMProfileTests.cs at line 1016 and inspect AzureRMProfileTests.LoadingProfileWorks. Compare the linked CI run and attached log across Windows and Linux; done means the test no longer intermittently produces the unexpected Byte[] value.

Written by the indexing model from the issue text.