Describe the Issue
Projects with absolute paths cannot be recognized by the solution filter.

Steps To Reproduce
1.Create a C# Console App, create a new solution file for it.
2.Add a C# ClassLibrary to the solution.
3.Configure a solution filter for two projects, then click 'Switch Solution' and open it.
4.Observe the solution filter in C# Project Details.
5.Open the solution file, modify the console project to use relative path, and then observe the C# Project Details.
Expected Behavior
In a solution that contains projects with both absolute and relative paths, the solution filter can recognize them simultaneously.
Environment Information
.NET Install Tool: 3.0.0
C# Dev Kit Extension: 3.14.196
C# Extension: 2.136.19
.NET SDKs: 11.0.100-preview.3.26207.106 & 10.0.203
VS Code Stable: 1.117.0
Platform: Windows X64
Describe the Issue
Projects with absolute paths cannot be recognized by the solution filter.

Steps To Reproduce
1.Create a C# Console App, create a new solution file for it.
2.Add a C# ClassLibrary to the solution.
3.Configure a solution filter for two projects, then click 'Switch Solution' and open it.
4.Observe the solution filter in C# Project Details.
5.Open the solution file, modify the console project to use relative path, and then observe the C# Project Details.
Expected Behavior
In a solution that contains projects with both absolute and relative paths, the solution filter can recognize them simultaneously.
Environment Information
.NET Install Tool: 3.0.0
C# Dev Kit Extension: 3.14.196
C# Extension: 2.136.19
.NET SDKs: 11.0.100-preview.3.26207.106 & 10.0.203
VS Code Stable: 1.117.0
Platform: Windows X64