remove unused imports

jme3-examples/src/main/java/jme3test/audio/TestReverb.java

@@ -35,7 +35,6 @@ import com.jme3.app.SimpleApplication;
 import com.jme3.audio.AudioData;
 import com.jme3.audio.AudioNode;
 import com.jme3.audio.Environment;
-import com.jme3.audio.LowPassFilter;
 import com.jme3.input.KeyInput;
 import com.jme3.input.controls.ActionListener;
 import com.jme3.input.controls.KeyTrigger;