Automatically insert a semicolon?

Question

JavaScript

Is there any online service / plugin for gulp that allows you to automatically put semicolons in js code with es6 support? I don't use them myself, but they are required by programmers who then work with my code. PS I'm doing the Front-end part.
To

let a = 1
let b = 2
console.log(a+b)

At the exit it was

let a = 1;
let b = 2;
console.log(a+b);