log/slog: use atomic.Pointer instead of atomic.Value
There is no need to use atomic.Value, atomic.Pointer should also
be more performant here.
Change-Id: I04cc1befbe1112665a9d9e16197ea3caef5e5fa3
GitHub-Last-Rev:
577902519ff744c936c5e707802f66aeae32c760
GitHub-Pull-Request: golang/go#62288
Reviewed-on: https://go-review.googlesource.com/c/go/+/523035
TryBot-Result: Gopher Robot <gobot@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Alan Donovan <adonovan@google.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
Run-TryBot: Mateusz Poliwczak <mpoliwczak34@gmail.com>