Don't implicitly run "pub get".

test/transformer/fails_to_load_a_transform_from_a_non_dependency_test.dart

Index: test/transformer/fails_to_load_a_transform_from_a_non_dependency_test.dart
diff --git a/test/transformer/fails_to_load_a_transform_from_a_non_dependency_test.dart b/test/transformer/fails_to_load_a_transform_from_a_non_dependency_test.dart
index 88e8b4aa5236ff7f737af24cbae80ff694114dd7..7af187c1b948bc02804ab75054d723985f6f2281 100644
--- a/test/transformer/fails_to_load_a_transform_from_a_non_dependency_test.dart
+++ b/test/transformer/fails_to_load_a_transform_from_a_non_dependency_test.dart
@@ -21,6 +21,7 @@ main() {
         })
       ]).create();
 
+      pubGet();
       var pub = startPubServe();
       pub.stderr.expect(contains('"foo" is not a dependency.'));
       pub.shouldExit(exit_codes.DATA);