internal/history: document Go 1.19.2 and 1.18.7 releases
internal/history: document Go 1.19.2 and 1.18.7 releases

Change-Id: I16189d677f83d3508aa3a6b4841b0e30b47312ca
Reviewed-on: https://go-review.googlesource.com/c/website/+/438180
Run-TryBot: Carlos Amedee <ab5e2bca84933118bbc9d48ffaccce3bac4eeb64@golang.org>
Reviewed-by: Dmitri Shuralyov <d181b7fea0ec87c86ba5a890ab716db52498e3ba@golang.org>
Reviewed-by: Dmitri Shuralyov <d181b7fea0ec87c86ba5a890ab716db52498e3ba@google.com>
Reviewed-by: Carlos Amedee <ab5e2bca84933118bbc9d48ffaccce3bac4eeb64@golang.org>

golang/website,golang/website,golang/website,golang/website,golang/website,golang/website,golang/website