Doesn't work with ESM

Trying to use quickchart-js in my TypeScript project and it just does not work because its not compatible with ESM

This is the error 

```
file:///C:/Users/pc/Desktop/node-quant/package/node_modules/quickchart-js/build/quickchart.mjs:192
    const fs = require("fs");
               ^

ReferenceError: require is not defined
```

Maybe its because the main export is a CJS module