Fix HDFS with AD auth for browse, read file scenarios (#6840)

* Fix HDFS with AD auth for browse, read
- HDFS now fully supports expanding nodes for all levels, including using cookie for auth
- HDFS now support reading files from HDFS
- HDFS write file is broken and will be fixed (either in PR update or separate PR)
- Removed hack to use gateway-0 instead of actual DNS name now these are supported. Needed for testing

* Fix Jupyter error using new DMV with endpoints

extensions/mssql/src/objectExplorerNodeProvider/fileSources.ts

@@ -16,7 +16,6 @@ import * as nls from 'vscode-nls';
 
 import * as constants from '../constants';
 import { WebHDFS, HdfsError } from './webhdfs';
-import * as auth from '../util/auth';
 
 const localize = nls.loadMessageBundle();
 
@@ -124,10 +123,6 @@ export class FileSourceFactory {
 			requestParams['agent'] = agent;
 
 		}
-		if (requestParams.isKerberos) {
-			let kerberosToken = await auth.authenticateKerberos(options.host);
-			requestParams.headers = { Authorization: `Negotiate ${kerberosToken}` };
-		}
 		return new HdfsFileSource(WebHDFS.createClient(options, requestParams));
 	}