Clean up some of the extensions (#8267)

* 💄

* prune unused code

* more cleanup

* remove abunch of used code

extensions/azurecore/src/azureResource/utils.ts

@@ -3,12 +3,10 @@
  *  Licensed under the Source EULA. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-'use strict';
-
 import * as nls from 'vscode-nls';
 const localize = nls.loadMessageBundle();
 
-export function getErrorMessage(error: Error | string): string {
+function getErrorMessage(error: Error | string): string {
 	return (error instanceof Error) ? error.message : error;
 }
 
@@ -93,4 +91,4 @@ export function equals(one: any, other: any): boolean {
 		}
 	}
 	return true;
-}
+}