[x/blog] blog: update to the App Engine Go 1.14 runtime

Reference:

•	https://cloud.google.com/appengine/docs/standard/go/runtime

Change-Id: I473814311bbfbd57cd3195fbeccdb49b6b4d47a7
Reviewed-on: https://go-review.googlesource.com/c/blog/+/266738
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Alexander Rakoczy <alex@golang.org>
Reviewed-by: Carlos Amedee <carlos@golang.org>
X-Blog-Commit: e544dc6f8517f12485e715cc028c76690f57bc9e
diff --git a/blog/app.yaml b/blog/app.yaml
index 45a26b9..3d0f8c1 100644
--- a/blog/app.yaml
+++ b/blog/app.yaml
@@ -1,5 +1,5 @@
 service: blog
-runtime: go112
+runtime: go114
 
 env_variables:
   GOLANGORG_CHECK_COUNTRY: true