Allow WorkspacePaths to be empty if we're not in a workspace

We were previously adding the initial working directory as a fallback if
there was no workspace. However, this led to new VS Code windows (not in
a workspace) enumerating all files in the home directory (if that's what
the client had to default to, without a workspace folder). And this
could even spam permission requests on more secure systems such as
macOS. So we just need to let be an empty enumerable.

src/PowerShellEditorServices/Services/Extension/EditorOperationsService.cs

@@ -192,7 +192,8 @@ public async Task SaveFileAsync(string currentPath, string newSavePath)
         }
 
         // NOTE: This name is now outdated since we don't have a way to distinguish one workspace
-        // from another for the extension API.
+        // from another for the extension API. TODO: Should this be an empty string if we have no
+        // workspaces?
         public string GetWorkspacePath() => _workspaceService.InitialWorkingDirectory;
 
         public string[] GetWorkspacePaths() => _workspaceService.WorkspacePaths.ToArray();

src/PowerShellEditorServices/Services/Workspace/WorkspaceService.cs

@@ -104,9 +104,7 @@ public WorkspaceService(ILoggerFactory factory)
 
         #region Public Methods
 
-        public IEnumerable<string> WorkspacePaths => WorkspaceFolders.Count == 0
-                ? new List<string> { InitialWorkingDirectory }
-                : WorkspaceFolders.Select(i => i.Uri.GetFileSystemPath());
+        public IEnumerable<string> WorkspacePaths => WorkspaceFolders.Select(i => i.Uri.GetFileSystemPath());
 
         /// <summary>
         /// Gets an open file in the workspace. If the file isn't open but exists on the filesystem, load and return it.