Add title to image export options dialog

Change-Id: I79e6722f2cfa8aabe3b3cacefe97d34063965d5d
Reviewed-on: https://gerrit.libreoffice.org/19812Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Katarina Behrens <Katarina.Behrens@cib.de>

svtools/uiconfig/ui/GraphicExportOptionsDialog.ui

@@ -15,6 +15,7 @@
   <object class="GtkDialog" id="GraphicExporter">
     <property name="can_focus">False</property>
     <property name="border_width">6</property>
+    <property name="title" translatable="yes">Image Options</property>
     <property name="type_hint">dialog</property>
     <child internal-child="vbox">
       <object class="GtkBox" id="dialog-vbox1">