[x/blog] go.blog: make december 1 blog posts cyclicly-referential

R=dsymonds
https://golang.org/cl/34640044
X-Blog-Commit: 005aafa63f16a353e775136f95cea69d07373d1f

blog/content/go12.article

@@ -71,6 +71,6 @@ submitted bug reports to the 116 (!) contributors who committed more than 1600
 changes to the core: Your help is invaluable to the project. Thank you!
 
 _This_blog_post_is_the_first_of_the_
-[[http://blog.gopheracademy.com/go-advent-2013][Go Advent Calendar]],
+[[http://blog.gopheracademy.com/day-01-go-1.2][Go Advent Calendar]],
 _a_series_of_daily_articles_presented_by_the_
 [[http://gopheracademy.com/][Gopher Academy]] _from_December_1_to_25._