fix bug in read_input_item_test.cpp

Author: mohanchen

source/source_io/test_serial/read_input_item_test.cpp

@@ -968,9 +968,9 @@ TEST_F(InputTest, Item_test2)
         output = testing::internal::GetCapturedStdout();
         EXPECT_THAT(output, testing::HasSubstr("NOTICE"));
     }
-    { // out_interval
-        auto it = find_label("out_interval", readinput.input_lists);
-        param.input.out_interval = 0;
+    { // out_freq_ion
+        auto it = find_label("out_freq_ion", readinput.input_lists);
+        param.input.out_freq_ion = 0;
         testing::internal::CaptureStdout();
         EXPECT_EXIT(it->second.check_value(it->second, param), ::testing::ExitedWithCode(1), "");
         output = testing::internal::GetCapturedStdout();