Remove unused LINQ using

Author: tanchekwei

WorkspaceLauncherForVSCode/Services/PinService.cs

@@ -1,7 +1,6 @@
 // Modifications copyright (c) 2025 tanchekwei
 // Licensed under the MIT License. See the LICENSE file in the project root for details.
 using System;
-using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.CommandPalette.Extensions;
 using Microsoft.CommandPalette.Extensions.Toolkit;

WorkspaceLauncherForVSCode/Services/VSWorkspaceWatcherService.cs

@@ -3,7 +3,6 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
-using System.Linq;
 using System.Threading;
 using WorkspaceLauncherForVSCode.Classes;
 using WorkspaceLauncherForVSCode.Interfaces;