Close new marketplace window when signing out or in

Because otherwise you can either see plugins you might not have the rights to, or not see plugins you do have the rights to.

part of CURA-8556

plugins/Marketplace/resources/qml/Marketplace.qml

@@ -7,6 +7,7 @@ import QtQuick.Layouts 1.15
 import QtQuick.Window 2.2
 
 import UM 1.2 as UM
+import Cura 1.6 as Cura
 
 Window
 {
@@ -18,18 +19,18 @@ Window
     width: minimumWidth
     height: minimumHeight
 
-    onVisibleChanged:
+    // Set and unset the content. No need to keep things in memory if it's not visible.
+    onVisibleChanged: content.source = visible ? "Plugins.qml" : ""
+
+    Connections
     {
-        // Set and unset the content. No need to keep things in memory if it's not visible. 
-        if(visible)
-        {
-            content.source = "plugins.qml"
-        }
-        else
+        target: Cura.API.account
+        function onLoginStateChanged()
         {
-            content.source = ""
+            close();
         }
     }
+
     title: "Marketplace" //Seen by Ultimaker as a brand name, so this doesn't get translated.
     modality: Qt.NonModal