Fix zip tests

Fix error when building zip tests running go test ./...:
android/soong/third_party/zip/zip_test.go:13:2: use of internal package not allowed

Test: go test ./...
Change-Id: I4fd7317401fd3d9c95c6f11799c94c1eff25523e
diff --git a/third_party/zip/zip_test.go b/third_party/zip/zip_test.go
index 3a3c915..7373660 100644
--- a/third_party/zip/zip_test.go
+++ b/third_party/zip/zip_test.go
@@ -10,7 +10,6 @@
 	"bytes"
 	"fmt"
 	"hash"
-	"internal/testenv"
 	"io"
 	"io/ioutil"
 	"sort"
@@ -20,7 +19,7 @@
 )
 
 func TestOver65kFiles(t *testing.T) {
-	if testing.Short() && testenv.Builder() == "" {
+	if testing.Short() {
 		t.Skip("skipping in short mode")
 	}
 	buf := new(bytes.Buffer)