src/go.mod, net/http: update bundled+latest golang.org/x/net
Updates x/net/http2 to git rev
89f602b7bbf237abe0467031a18b42fc742ced08
http2: validate client/outgoing trailers
https://golang.org/cl/572655 (updates #64766)
and also updates the vendored version of golang.org/x/net per:
$ go get golang.org/x/net@
89f602b7bb
$ go mod tidy
$ go mod vendor
$ go generate -run bundle std
Change-Id: Ibd0e819d9125e72665bafec53ba626e257b594a5
Reviewed-on: https://go-review.googlesource.com/c/go/+/572676
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Damien Neil <dneil@google.com>
Auto-Submit: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
TryBot-Result: Gopher Robot <gobot@golang.org>