Fix the button to open Store page

The button to open the Store page was always active, regardless of whether the package was from store or from side-loading.

src/Otor.MsixHero.App/Modules/PackageManagement/Commands/PackagesManagementCommandHandler.cs

@@ -848,7 +848,7 @@ private async void OnRemovePackage()
 
         private bool CanRemovePackage() => this.IsAnySelected();
 
-        private bool CanOpenStore() => this.IsSingleSelected();
+        private bool CanOpenStore() => this.IsSingleSelected() && this.application.ApplicationState.Packages.SelectedPackages.FirstOrDefault()?.SignatureKind == SignatureKind.Store;
 
         private bool CanOpenPsfConfig()
         {