all: use the indefinite article an in comments
This is a follow up of CL 530120.
Change-Id: Ifa0bd1c3bb9bb1202568eaae27500bcea376f56b
GitHub-Last-Rev:
b4154fa1fc205a6a1af050ab49a4738f73b3c32a
GitHub-Pull-Request: golang/go#63228
Reviewed-on: https://go-review.googlesource.com/c/go/+/531136
Auto-Submit: Bryan Mills <bcmills@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>