Revert bad change to objc conformance test in #6199
Revert bad change to objc conformance test in #6199

Since true for objc is external, changes should always start on the github
side, so the fact that something got pushed out is a sign something was
broken in the process.

google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf