Can’t add files with `Project.addSourceFilesAtPaths()`

[rojvv]

Describe the bug

Version: 19.0.0

To Reproduce

import { Project } from "ts-morph";

const project = new Project();

project.addSourceFilesAtPaths(["a/x.ts", "a/y.ts"]);

Expected behavior

Must behave like adding each file individually with Project.addSourceFileAtPath().