Notebooks: Save connection information in metadata (#13060)

* save connection info in notebook metadata

* update attachTo dropdown based on saved alias

* add setting for saving connection (default=false)

* dont show saved conn if seting off + added test

* show conn dialog if save conn name setting off

* address PR comments and fix unit test

* change connectionName to connection_name

src/sql/workbench/contrib/notebook/browser/notebook.contribution.ts

@@ -230,7 +230,12 @@ configurationRegistry.registerConfiguration({
 			'type': 'boolean',
 			'default': true,
 			'description': localize('notebook.setRichTextViewByDefault', "Set Rich Text View mode by default for text cells")
-		}
+		},
+		'notebook.saveConnectionName': {
+			'type': 'boolean',
+			'default': false,
+			'description': localize('notebook.saveConnectionName', "(Preview) Save connection name in notebook metadata.")
+		},
 	}
 });