In Webpack 5, the [recommended way](https://webpack.js.org/guides/web-workers/) to create a web worker is

```ts
new Worker(new URL('./worker.js', import.meta.url));
```

Could we update\* the [`pdfjs-dist/webpack` entrypoint](https://github.com/mozilla/pdfjs-dist/blob/master/webpack.js) to use this syntax instead of the legacy `worker-loader`? One of the Webpack contributors told me that `worker-loader` uses "magic" and can cause issues.

\* To maintain compatibility with people still using Webpack 4, we should probably introduce a new entrypoint called `pdfjs-dist/webpack5` (or something like that) rather than changing the existing entrypoint.

Can attempt a PR if you would like.

Closely-related: https://github.com/mozilla/pdf.js/issues/15302


console.log();
  console.log("### Creating baseline environment");
  const baselineCommit = process.env.BASELINE;
  if (!baselineCommit) {
    done(new Error("Missing baseline commit. Specify the BASELINE variable."));
    return;
  }
  let initializeCommand = "git fetch origin";
  if (!checkDir(BASELINE_DIR)) {
    mkdirp.sync(BASELINE_DIR);
    initializeCommand = "git clone ../../ .";
  }
  const workingDirectory = path.resolve(process.cwd(), BASELINE_DIR);
  exec(initializeCommand, { cwd: workingDirectory }, function (error) {
    if (error) {
      done(new Error("Baseline clone/fetch failed."));
      return;
    }
    exec(
      "git checkout " + baselineCommit,
      { cwd: workingDirectory },
      function (error2) {
        if (error2) {
          done(new Error("Baseline commit checkout failed."));
          return;
        }
        console.log('Baseline commit "' + baselineCommit + '" checked out.');
        done();