go1.14beta1: fix link to release notes

Change-Id: I1e3a9e2ce449fe106194cc4c9ac918180821c15a
Reviewed-on: https://go-review.googlesource.com/c/dl/+/211697
Reviewed-by: Alexander Rakoczy <alex@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
1 file changed