[epiphany] Add missing F12 key for Toggle inspector

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 77e568beb78e2576fcf8cc25dc3d336dc3427027
Author: Sabri Ünal <libreajans gmail com>
Date:   Thu Jan 30 14:15:14 2020 +0300

    Add missing F12 key for Toggle inspector

 src/resources/gtk/shortcuts-dialog.ui | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/resources/gtk/shortcuts-dialog.ui b/src/resources/gtk/shortcuts-dialog.ui
index eaccb93e8..57a4d31c9 100644
--- a/src/resources/gtk/shortcuts-dialog.ui
+++ b/src/resources/gtk/shortcuts-dialog.ui
@@ -294,7 +294,7 @@
               <object class="GtkShortcutsShortcut">
                 <property name="visible">True</property>
                 <property name="title" translatable="yes" context="shortcut window">Toggle 
inspector</property>
-                <property name="accelerator">&lt;shift&gt;&lt;Primary&gt;I</property>
+                <property name="accelerator">&lt;shift&gt;&lt;Primary&gt;I F12</property>
               </object>
             </child>
             <child>