Fix unused variable warning.

GitOrigin-RevId: 6b6564fcf9f5cce91630d1888d7e95b187bfc320
diff --git a/tests/FuzzerUnittest.cpp b/tests/FuzzerUnittest.cpp
index 1251a4e..7c6ecfb 100644
--- a/tests/FuzzerUnittest.cpp
+++ b/tests/FuzzerUnittest.cpp
@@ -671,6 +671,7 @@
                      /*TimeOfUnit*/ std::chrono::microseconds(5678),
                      /*FeatureSet*/ {}, DFT,
                      /*BaseII*/ nullptr);
+  (void) SecondII;
   Unit ReplacedU = Unit{0x03};
 
   C->Replace(FirstII, ReplacedU,