Add check plugin update button

Flow.Launcher/Languages/en.xaml

@@ -237,6 +237,7 @@
     <system:String x:Key="updateNoResultSubtitle">All plugins are up to date</system:String>
     <system:String x:Key="updateAllPluginsTitle">Update all plugins</system:String>
     <system:String x:Key="updateAllPluginsSubtitle">Would you like to update these plugins?{0}{0}{1}</system:String>
+    <system:String x:Key="checkPluginUpdatesTooltip">Check plugin updates</system:String>
 
     <!--  Setting Theme  -->
     <system:String x:Key="theme">Theme</system:String>

Flow.Launcher/SettingPages/ViewModels/SettingsPanePluginStoreViewModel.cs

@@ -109,6 +109,12 @@ public partial class SettingsPanePluginStoreViewModel : BaseModel
             await PluginInstaller.InstallPluginAndCheckRestartAsync(file);
     }
 
+    [RelayCommand]
+    private async Task CheckPluginUpdatesAsync()
+    {
+        await PluginInstaller.UpdatePluginAsync(silentUpdate: false);
+    }
+
     private static string GetFileFromDialog(string title, string filter = "")
     {
         var dlg = new Microsoft.Win32.OpenFileDialog

Flow.Launcher/SettingPages/Views/SettingsPanePluginStore.xaml

@@ -99,6 +99,13 @@
                     ToolTip="{DynamicResource installLocalPluginTooltip}">
                     <ui:FontIcon FontSize="14" Glyph="&#xE8DA;" />
                 </Button>
+                <Button
+                    Height="34"
+                    Margin="0 0 10 0"
+                    Command="{Binding CheckPluginUpdatesCommand}"
+                    ToolTip="{DynamicResource checkPluginUpdatesTooltip}">
+                    <ui:FontIcon FontSize="14" Glyph="&#xecc5;" />
+                </Button>
                 <TextBox
                     Name="PluginStoreFilterTextbox"
                     Width="150"