_content/blog/go1.18beta1: add generics to headline

Change-Id: Icea98fad0e358fbbd01554a6c816a2e57b2150d7
Reviewed-on: https://go-review.googlesource.com/c/website/+/371895
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Steve Francia <sfrancia@google.com>
diff --git a/_content/blog/go1.18beta1.md b/_content/blog/go1.18beta1.md
index 6f2a7bf..365b6a5 100644
--- a/_content/blog/go1.18beta1.md
+++ b/_content/blog/go1.18beta1.md
@@ -1,5 +1,5 @@
 ---
-title: Go 1.18 Beta 1 is available
+title: Go 1.18 Beta 1 is available, with generics
 date: 2021-12-14
 by:
 - Russ Cox, for the Go team