Fix possible NPE in AbstractAzureFacetNode

Author: Flanker-MSFT

PluginsAndFeatures/azure-toolkit-for-intellij/azure-intellij-plugin-facet/src/main/java/com/microsoft/azure/toolkit/intellij/facet/projectexplorer/AbstractAzureFacetNode.java

@@ -106,6 +106,10 @@ private void rerender(boolean updateStructure) { // `static` to make it availabl
             return;
         }
         final AbstractProjectViewPane pane = ProjectView.getInstance(this.getProject()).getCurrentProjectViewPane();
+        if (Objects.isNull(pane) || Objects.isNull(pane.getTree())) {
+            Disposer.dispose(this);
+            return;
+        }
         final AsyncTreeModel model = (AsyncTreeModel) pane.getTree().getModel();
         final DefaultMutableTreeNode node = TreeUtil.findNodeWithObject((DefaultMutableTreeNode) model.getRoot(), this);
         if (Objects.nonNull(node)) {