修复escape末尾字符串丢失问题

package.json

@@ -1,6 +1,6 @@
 {
   "name": "yizhi-html-escape",
-  "version": "1.0.2",
+  "version": "1.0.3",
   "description": "HTML escape character util",
   "main": "dist/index.js",
   "types": "typing/index.d.ts",

src/index.ts

@@ -17,6 +17,7 @@ export function escape(str: string) {
 			prev = i + 1
 		}
 	}
+	buffer.push(str.substring(prev))
 	return buffer.join('')
 }