archive: use slices and maps to clean up tests
Replace reflect.DeepEqual with slices.Equal/maps.Equal, which is
much faster.
Clean up some unnecessary helper functions.
Change-Id: I9b94bd43886302b9b327539ab065a435ce0d75d9
GitHub-Last-Rev:
b9ca21f165bcc5e45733e6a511a2344b1aa4a281
GitHub-Pull-Request: golang/go#67607
Reviewed-on: https://go-review.googlesource.com/c/go/+/587936
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Joseph Tsai <joetsai@digital-static.net>