Fix BerksfileCheck spec to stub in_path?

This spec would pass locally but fail on Travis because it didn't stub
the `in_path?` call. Fix it.

Change-Id: I359f69518eae2f108761c6e48f2273a9b8cc146e
Reviewed-on: http://gerrit.causes.com/37940
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>
Fix BundleCheck spec to stub in_path?

This spec didn't stub the call to `in_path?` when it should have. It
worked because `bundler` is installed on Travis, but it is better form
to not make that assumption.

Change-Id: Ie974f5e22f55c3ab977c69f232e8667a4b34460c
Reviewed-on: http://gerrit.causes.com/37941
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>