Async methods should always return a Promise when using inlineHelpers

[edoardocavazza]

When using this plugin with inlineHelpers: true, async methods should always return a Promise also if not using the await keyword.

Example:

class MyClass {
    static async check() {
        return true;
    }
};

console.log(MyClass.check() instanceof Promise); // -> true

is transpiled to:

class MyClass {
    static check() {
         try {
             return true;
         } catch (e) {
             return Promise.reject(e);
         }
     }
}

console.log(MyClass.check() instanceof Promise); // -> false