This variable is not used anymore. It was used in the
TestPackageNotStaleWithTrailingSlash test.

Change-Id: I5e52d4d1d91592dd21e2d9cff96974a49d07f5f8
Reviewed-on: https://go-review.googlesource.com/126376
Run-TryBot: Yury Smolsky <yury@smolsky.by>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>