Mount HDFS Dialog: basic support (#7580)

Implemented in this PR

- New base dialog for anything needing to work with the controller. This is important since going from SQL -> Controller we "should" have the right permissions but aren't guaranteed
- Support for Mount HDFS via a dialog. Includes basic polling for success/failure, but have to give up after 2.5min as mounting could take hours. By then it's assumed to be successful since server-side has 2min timeout built in.


Not implemented in this PR

- Script as Notebook button. This should convert the inputs to a set of cells in a notebook so users can run things themselves
- Updates based on PM / UX reviews. I think we'll need a round of feedback before completing this work.

extensions/big-data-cluster/src/bigDataCluster/dialog/addControllerDialog.ts

@@ -10,7 +10,6 @@ import * as nls from 'vscode-nls';
 import { ClusterController, ControllerError } from '../controller/clusterControllerApi';
 import { ControllerTreeDataProvider } from '../tree/controllerTreeDataProvider';
 import { TreeNode } from '../tree/treeNode';
-import { showErrorMessage } from '../utils';
 import { AuthType } from '../constants';
 
 const localize = nls.loadMessageBundle();
@@ -177,7 +176,7 @@ export class AddControllerDialog {
 					],
 					title: ''
 				}]).withLayout({ width: '100%' }).component();
-
+			this.onAuthChanged();
 			await view.initializeModel(formModel);
 		});