all: update vendored golang.org/x/{net,tools} for Go 1.20 development

all: update vendored golang.org/x/{net,tools} for Go 1.20 development

CL 421334 updated most of golang.org/x dependencies at the start of
the Go 1.20 development cycle. This CL updates x/net and x/tools as
well, now that go.dev/issue/54259 is resolved.

For #36905.
Updates #54259.

Change-Id: Ie422b71cba060a4774076eebf3b499cda1150367
Reviewed-on: https://go-review.googlesource.com/c/go/+/421461
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>