Fixed crash of Eclipse while event selection ...

plugins/org.yakindu.sct.simulation.ui/src/org/yakindu/sct/simulation/ui/view/DeclarationView.java

@@ -29,8 +29,6 @@ import org.eclipse.jface.viewers.TreeViewer;
 import org.eclipse.jface.viewers.TreeViewerColumn;
 import org.eclipse.jface.viewers.Viewer;
 import org.eclipse.swt.SWT;
-import org.eclipse.swt.events.MouseEvent;
-import org.eclipse.swt.events.MouseListener;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Display;
 import org.yakindu.sct.simulation.core.debugmodel.SCTDebugTarget;