os: remove mixed dot- and non-dot- imports in tests
Some test files imported "os" twice, once with a dot and once without.
Consolidate on importing with a dot.
Change-Id: I1db31053dff9dee19a6bdfc263c7e7ef0c15ee42
Reviewed-on: https://go-review.googlesource.com/c/go/+/479995
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com> Reviewed-by: Robert Griesemer <gri@google.com> Reviewed-by: Ian Lance Taylor <iant@google.com>