[gnome-contacts] ContactEditor: fix annoying const warning.

[Niels De Graef <nielsdg src gnome org>]

commit 310aaf04661b5436c1a29cb1eae4bf7d8a5288cc
Author: Niels De Graef <nielsdegraef gmail com>
Date:   Mon Nov 13 21:12:52 2017 +0100

    ContactEditor: fix annoying const warning.
    
    Was going to postpone this after the editor rewrite, but would like to
    keep most of the warnings out of the releases (or as much as possible).

 src/contacts-contact-editor.vala |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/contacts-contact-editor.vala b/src/contacts-contact-editor.vala
index 1b6cbc5..1540db8 100644
--- a/src/contacts-contact-editor.vala
+++ b/src/contacts-contact-editor.vala
@@ -24,7 +24,7 @@ public class Contacts.AddressEditor : Box {
   public Entry? entries[7];  /* must be the number of elements in postal_element_props */
   public PostalAddressFieldDetails details;
 
-  public static const string[] postal_element_props = {"street", "extension", "locality", "region", 
"postal_code", "po_box", "country"};
+  public const string[] postal_element_props = {"street", "extension", "locality", "region", "postal_code", 
"po_box", "country"};
   public static string[] postal_element_names = {_("Street"), _("Extension"), _("City"), 
_("State/Province"), _("Zip/Postal Code"), _("PO box"), _("Country")};
 
   public signal void changed ();