[feat] add class support

[Isaw-w]

Hi I just add class support for LikeButtonSdk

example

import LikeCoinButton from './sdk.esm.js';

const likeCoinButton = new LikeCoinButton({
  likerId: 'guanyun',
  ref: '.my-like-button',
});

likeCoinButton.mount();

[nnkken]

The code looks good, please fix the eslint warnings / errors.

[Isaw-w]

eslint issue has been fixed! 🖖🏽