Normalize local DescriptionLocation to use / as directory separator

[ajtribick]

This seems to be the most straightforward way of solving the issue where Windows paths fail on Linux machines, unless there are some systems which don't use the forward slash as a path separator?

Resolves #4228

[ajtribick]

@microsoft-github-policy-service agree

[baywet]

Thanks for starting the work on this one.
A couple of requests:

• Can you add an entry to the changelog
• Can you make similar changes to the workspace management? (we're in the process of migrating to a new centralized way of managing client configurations)

[ajtribick]

I think this should do it. Not sure about the placement/visibility of the extension method, let me know if you have any preferences there.

[baywet]

Thanks for making the changes!