removed extra comma

lib/single-file/serializer.js

@@ -49,7 +49,7 @@ this.serializer = this.serializer || (() => {
 		{ tagName: "tfoot", accept: next => !next },
 		{ tagName: "tr", accept: next => !next || ["TR"].includes(next.tagName) },
 		{ tagName: "td", accept: next => !next || ["TD", "TH"].includes(next.tagName) },
-		{ tagName: "th", accept: next => !next || ["TD", "TH"].includes(next.tagName) },
+		{ tagName: "th", accept: next => !next || ["TD", "TH"].includes(next.tagName) }
 	];
 
 	return {