PluginRegistry was not correctly initialised for the tests

Author: Hirogen

src/LogExpert.Tests/Services/FileOperationServiceTests.cs

@@ -37,6 +37,13 @@ internal class FileOperationServiceTests : IDisposable
 
     private bool _disposed;
 
+    [OneTimeSetUp]
+    public void OneTimeSetUp ()
+    {
+        var dir = Path.GetDirectoryName(typeof(FileOperationServiceTests).Assembly.Location)!;
+        _ = PluginRegistry.PluginRegistry.Create(dir, 500);
+    }
+
     [SetUp]
     public void Setup ()
     {

src/LogExpert.UI/Services/FileOperationService/FileOperationService.cs

@@ -331,8 +331,8 @@ public void LoadStartupFiles (IList<string> lastOpenFiles, string[]? startupFile
             {
                 _ = AddFileTab(new FileTabRequest { FileName = name });
             }
-        }
 
-        _configManager.ClearLastOpenFilesList();
+            _configManager.ClearLastOpenFilesList();
+        }
     }
 }