Remove useless interface

Source/LibationAvalonia/ViewModels/Settings/AudioSettingsVM.cs

@@ -8,7 +8,7 @@ using System.Linq;
 
 namespace LibationAvalonia.ViewModels.Settings
 {
-	public class AudioSettingsVM : ViewModelBase, ISettingsDisplay
+	public class AudioSettingsVM : ViewModelBase
 	{
 		private bool _downloadClipsBookmarks;
 		private bool _decryptToLossy;

Source/LibationAvalonia/ViewModels/Settings/DownloadDecryptSettingsVM.cs

@@ -5,7 +5,7 @@ using System.Collections.Generic;
 
 namespace LibationAvalonia.ViewModels.Settings
 {
-	public class DownloadDecryptSettingsVM : ViewModelBase, ISettingsDisplay
+	public class DownloadDecryptSettingsVM : ViewModelBase
 	{
 		private string _folderTemplate;
 		private string _fileTemplate;

Source/LibationAvalonia/ViewModels/Settings/ImportSettingsVM.cs

@@ -2,7 +2,7 @@
 
 namespace LibationAvalonia.ViewModels.Settings
 {
-	public class ImportSettingsVM : ISettingsDisplay
+	public class ImportSettingsVM
 	{
 		public ImportSettingsVM(Configuration config)
 		{

Source/LibationAvalonia/ViewModels/Settings/ImportantSettingsVM.cs

@@ -1,5 +1,4 @@
-using Avalonia.Controls.Shapes;
-using FileManager;
+using FileManager;
 using LibationFileManager;
 using ReactiveUI;
 using System;
@@ -7,7 +6,7 @@ using System.Collections.Generic;
 
 namespace LibationAvalonia.ViewModels.Settings
 {
-	public class ImportantSettingsVM : ViewModelBase, ISettingsDisplay
+	public class ImportantSettingsVM : ViewModelBase
 	{
 		private string themeVariant;
 		private string initialThemeVariant;

Source/LibationAvalonia/ViewModels/Settings/SettingsVM.cs

@@ -2,13 +2,7 @@
 
 namespace LibationAvalonia.ViewModels.Settings
 {
-	internal interface ISettingsDisplay
-	{
-		void LoadSettings(Configuration config);
-		void SaveSettings(Configuration config);
-	}
-
-	public class SettingsVM : ISettingsDisplay
+	public class SettingsVM
 	{
 		public SettingsVM(Configuration config)
 		{