removed unneeded parenthesis

lib/single-file/single-file-core.js

@@ -426,7 +426,7 @@ this.SingleFileCore = this.SingleFileCore || (() => {
 
 		async frames(initialization) {
 			const frameElements = Array.from(this.doc.querySelectorAll("iframe, frame, object[type=\"text/html\"][data]"));
-			await Promise.all(frameElements.map(async (frameElement) => {
+			await Promise.all(frameElements.map(async frameElement => {
 				const frameWindowId = frameElement.getAttribute(WIN_ID_ATTRIBUTE_NAME);
 				if (frameWindowId) {
 					const frameData = this.options.framesData.find(frame => frame.windowId == frameWindowId);