[gnome-tweak-tool] shell proxy extensions: fix typo (missing 's')

[John Stowers <jstowers src gnome org>]

commit 7772871d5f6d73b165968d3c1d11dbaa25b3e785
Author: Alban Browaeys <prahal yahoo com>
Date:   Mon Aug 13 12:25:03 2012 +0200

    shell proxy extensions: fix typo (missing 's')
    
    https://bugzilla.gnome.org/show_bug.cgi?id=681761

 gtweak/gshellwrapper.py |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtweak/gshellwrapper.py b/gtweak/gshellwrapper.py
index 575b005..d458cff 100644
--- a/gtweak/gshellwrapper.py
+++ b/gtweak/gshellwrapper.py
@@ -37,7 +37,7 @@ class _ShellProxy:
                             None)
 
         #GNOME Shell > 3.5 added a separate extension interface
-        self.proxy_extension = Gio.DBusProxy.new_sync(
+        self.proxy_extensions = Gio.DBusProxy.new_sync(
                             d, 0, None,
                             'org.gnome.Shell',
                             '/org/gnome/Shell',