Skip formatting when during format-on-save, the configured formatter …

…cannot be found (continue to show silent notification), #106376

src/vs/editor/contrib/format/format.ts

@@ -116,7 +116,7 @@ export abstract class FormattingConflicts {
 		if (selector) {
 			return await selector(formatter, document, mode);
 		}
-		return formatter[0];
+		return undefined;
 	}
 }
 

src/vs/workbench/contrib/format/browser/formatActionsMultiple.ts

@@ -121,7 +121,7 @@ class DefaultFormatter extends Disposable implements IWorkbenchContribution {
 			if (silent) {
 				// don't wait when formatting happens without interaction
 				// but pick some formatter...
-				resolve(formatter[0]);
+				resolve(undefined);
 			}
 		});
 	}