enhance: refresh submodules after .gitmodules file changed

Signed-off-by: leo <longshuang@msn.cn>

Author: love-linger

src/Models/Watcher.cs

@@ -187,9 +187,15 @@ private void OnWorkingCopyChanged(object o, FileSystemEventArgs e)
                 return;
 
             var name = e.Name.Replace("\\", "/");
-            if (name == ".git" || name.StartsWith(".git/", StringComparison.Ordinal))
+            if (name.Equals(".git", StringComparison.Ordinal) || name.StartsWith(".git/", StringComparison.Ordinal))
                 return;
 
+            if (name.Equals(".gitmodules", StringComparison.Ordinal))
+            {
+                _updateSubmodules = DateTime.Now.AddSeconds(1).ToFileTime();
+                return;
+            }
+
             lock (_lockSubmodule)
             {
                 foreach (var submodule in _submodules)