[gnome-online-accounts] doc: Update copyright notice

[Debarshi Ray <debarshir src gnome org>]

commit 41e7e96ec1159deb90948c8a451319d51a43e6c4
Author: Debarshi Ray <debarshir gnome org>
Date:   Fri Jun 16 17:04:57 2017 +0200

    doc: Update copyright notice
    
    Use a range instead of listing individual years like we do elsewhere.

 doc/goa-docs.xml |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/doc/goa-docs.xml b/doc/goa-docs.xml
index 987327f..e762c40 100644
--- a/doc/goa-docs.xml
+++ b/doc/goa-docs.xml
@@ -29,7 +29,7 @@
     </authorgroup>
 
     <copyright>
-      <year>2011, 2012</year>
+      <year>2011 – 2017</year>
       <holder>The GOA Authors</holder>
     </copyright>