content: fix typo in 10years.article

Change-Id: Ibeccb23861fceafcde66638c7f0f47bbdc2db7d9
GitHub-Last-Rev: cb7e3221d9358e0ea4467a559e509de581bff73b
GitHub-Pull-Request: golang/blog#27
Reviewed-on: https://go-review.googlesource.com/c/blog/+/206177
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/content/10years.article b/content/10years.article
index fa094f9..4a33db0 100644
--- a/content/10years.article
+++ b/content/10years.article
@@ -86,7 +86,7 @@
 a production-quality implementation,
 a
 [[https://blog.golang.org/ismmkeynote][state-of-the-art garbage collector]],
-and [[https://golang.org/doc/install/source#introduction][ports to a 12 operating systems and 10 architectures]].
+and [[https://golang.org/doc/install/source#introduction][ports to 12 operating systems and 10 architectures]].
 
 Any programming language needs the support of a thriving ecosystem.
 The open source release was the seed for that ecosystem,