SpaceAnalyzer: Stop treating selecting a node as a path change

This served no obvious purpose, but did make the breadcrumb bar change
confusingly.

Userland/Applications/SpaceAnalyzer/TreeMapWidget.cpp

@@ -304,9 +304,6 @@ void TreeMapWidget::mousedown_event(GUI::MouseEvent& event)
         if (!path.is_empty()) {
             m_path_segments.shrink(m_viewpoint);
             m_path_segments.extend(path);
-            if (on_path_change) {
-                on_path_change();
-            }
             update();
         }
     }