VisualStudioCodeCredentials does not work on WSL2 [BUG]

[tshaiman]

Describe the bug
when working against Cosmos Db with VisualStudioCodeCredentials (after login to the Azure Subscription)
The following exception is thrown :

Exception has occurred: CLR/Azure.Identity.CredentialUnavailableException
An exception of type 'Azure.Identity.CredentialUnavailableException' occurred in System.Private.CoreLib.dll but was not handled in user code: 'Stored credentials not found. Need to authenticate user in VSCode Azure Account.'

The same code with the same Azure Subscription after login is working on Windows.

Expected behavior

• VisualStudioCodeCredentials should work in WSL2

Actual behavior (include Exception or Stack Trace)
Exception is thrown :

Exception has occurred: CLR/Azure.Identity.CredentialUnavailableException
An exception of type 'Azure.Identity.CredentialUnavailableException' occurred in System.Private.CoreLib.dll but was not handled in user code: 'Stored credentials not found. Need to authenticate user in VSCode Azure Account.'
 Inner exceptions found, see $exception in variables window for more details.
 Innermost exception 	 System.NullReferenceException : Object reference not set to an instance of an object.
   at Azure.Identity.VisualStudioCodeCredential.IsRefreshTokenString(String str)
   at Azure.Identity.VisualStudioCodeCredential.GetStoredCredentials(String environmentName)

To Reproduce
Steps to reproduce the behavior (include a code snippet, screenshot, or any additional information that might help us reproduce the issue)

1. Open VS Code in WSL2 , and login to Azure Subscription using the Azure Account Plugin
2. Run a sample code that uses VisualStudioCodeCredentials for example

var cosmosClient = new CosmosClient(endpoint, new Azure.Identity.VisualStudioCodeCredential());

Environment:
Azure.Identity 1.4.1 , Microsoft.Azure.Cosmos 3.20.1
OS Name: ubuntu
OS Version: 18.04
OS Platform: Linux
.Net Sdk 5.0.301
Vs Code Version 1.60.0

[jsquire]

Thank you for your feedback. Tagging and routing to the team members best able to assist.

[christothes]

closing until #30525 is addressed