security: cleanup validation error reporting

Change-Id: I313bedb336ecfb4180ba0f31ad77666544ba1c10
diff --git a/tests/unit/security/validator-fixture.hpp b/tests/unit/security/validator-fixture.hpp
index 25cbe93..b225c53 100644
--- a/tests/unit/security/validator-fixture.hpp
+++ b/tests/unit/security/validator-fixture.hpp
@@ -68,7 +68,7 @@
   util::DummyClientFace face{m_io, {true, true}};
   std::function<void(const Interest&)> processInterest;
   CertificateCache cache{100_days};
-  ValidationError lastError{ValidationError::Code::NO_ERROR};
+  ValidationError lastError{ValidationError::NO_ERROR};
 
 private:
   const static time::milliseconds s_mockPeriod;