The Group function takes a key and a ...any, which is converted
into attrs.
Fixes#59204.
Change-Id: Ib714365dcda2eda37863ce433f3dd8cf5eeda610
Reviewed-on: https://go-review.googlesource.com/c/go/+/487855
Reviewed-by: Alan Donovan <adonovan@google.com>
Run-TryBot: Jonathan Amsterdam <jba@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>