Use "old" AssertJ assertion for IllegalArgumentException

Author: Jochen Schalanda

src/test/java/org/graylog/plugins/netflow/codecs/NetFlowCodecTest.java

@@ -32,7 +32,6 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
-import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
 
 public class NetFlowCodecTest {
     @Rule
@@ -112,7 +111,7 @@ public void constructorFailsIfNetFlow9DefinitionsPathIsInvalidYaml() throws Exce
                 NetFlowCodec.CK_NETFLOW9_DEFINITION_PATH, definitionsFile.getAbsolutePath());
         final Configuration configuration = new Configuration(configMap);
 
-        assertThatIllegalArgumentException()
+        assertThatExceptionOfType(IllegalArgumentException.class)
                 .isThrownBy(() -> new NetFlowCodec(configuration, Executors.newSingleThreadScheduledExecutor(), objectMapper))
                 .withMessageMatching("Unable to parse NetFlow 9 definitions");
     }