os: document that WriteFile is not atomic
Fixes #56173
Change-Id: I03a3ad769c99c0bdb78b1d757173d630879fd4dd
GitHub-Last-Rev:
e3e31fa0b95aba363b13c45f562e3a4c8b31f2cc
GitHub-Pull-Request: golang/go#56282
Reviewed-on: https://go-review.googlesource.com/c/go/+/443495
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>