message: build: fix build break in
  Some absl::optional changes missed due to not being merged with
diff: @@ -929,7 +929,7 @@ TEST_F(HttpConnectionManagerImplTest, TestAccessLogWithInvalidRequest) {
  EXPECT_CALL(*handler, log(_, _, _))
  .WillOnce(Invoke(
  [](const HeaderMap*, const HeaderMap*, const RequestInfo::RequestInfo& request_info) {
  - EXPECT_TRUE(request_info.responseCode().valid());
  + EXPECT_TRUE(request_info.responseCode());
  EXPECT_EQ(request_info.responseCode().value(), uint32_t(400));
  EXPECT_NE(nullptr, request_info.downstreamLocalAddress());
  EXPECT_NE(nullptr, request_info.downstreamRemoteAddress());
  