UpdateDownloadDialog.qml: set `autoClose` to false

The `autoClose` property was set to the default value of `true`.
This causes an issue where if a user refocuses the Jami window, the
update dialog closes and cancels the update.

Gitlab: #1934
Change-Id: Ia7a90875702a0998de71133ed2215fb0583e161e

src/app/settingsview/components/UpdateDownloadDialog.qml

@@ -34,6 +34,7 @@ SimpleMessageDialog {
     property alias progressBarValue: progressBar.value
 
     closeButtonVisible: false
+    autoClose: false
 
     button1.text: JamiStrings.optionCancel
     button1Role: DialogButtonBox.RejectRole