doc/go1.20: add a release note for multiple error wrapping
doc/go1.20: add a release note for multiple error wrapping

For #53435.

Change-Id: I894bd645b0b61d7dd5f3aae7d1ea7b8a12f31dd8
Reviewed-on: https://go-review.googlesource.com/c/go/+/450376
Run-TryBot: Damien Neil <7e091e9a80da888fcd7836fd3c6b7b85f4677c12@google.com>
TryBot-Result: Gopher Robot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@google.com>

golang/go,golang/go,golang/go,golang/go,golang/go,golang/go,golang/go,golang/go