[gedit] help: Add translator comment about Alt+O in keyboard shortcuts

[Andre Klapper <aklapper src gnome org>]

commit cd2993af5529c4a93804ac620b47e45922da4563
Author: Andre Klapper <a9016009 gmx de>
Date:   Wed Feb 12 18:23:00 2020 +0100

    help: Add translator comment about Alt+O in keyboard shortcuts
    
    See #269

 help/C/gedit-shortcut-keys.page | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/help/C/gedit-shortcut-keys.page b/help/C/gedit-shortcut-keys.page
index 4da21d0dd..5c72afc09 100644
--- a/help/C/gedit-shortcut-keys.page
+++ b/help/C/gedit-shortcut-keys.page
@@ -129,7 +129,7 @@
         </tr>
         <tr>
            <td><p>Open the <gui>Quick Open</gui> window</p></td>
-           <td><p><keyseq><key>Alt</key><key>O</key></keyseq></p></td>
+           <td><p><keyseq><key>Alt</key><key xmlns:its="http://www.w3.org/2005/11/its"; 
its:locNote="Translators: Do not blindly translate this to 'O': It is likely wrong! The letter 'O' depends on 
your translation of msgid '_Open' in the gedit UI! It is the letter after the 
underscore.">O</key></keyseq></p></td>
         </tr>
         <tr>
           <td><p>Save the current document</p></td>