CONTRIBUTORS: update for the Go 1.17 release

This update was created using the updatecontrib command:

	go get golang.org/x/build/cmd/updatecontrib
	cd gotip
	GO111MODULE=off updatecontrib

With manual changes based on publicly available information
to canonicalize letter case and formatting for a few names.

For #12042.

Change-Id: I96718c0fe438cd97b62499a027252748a1fa0779
Reviewed-on: https://go-review.googlesource.com/c/go/+/341709
Trust: Carlos Amedee <carlos@golang.org>
Run-TryBot: Carlos Amedee <carlos@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>