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


if (process.argv.includes("--noChrome") || forceNoChrome) {
    args.push("--noChrome");
  }
  const testProcess = startNode(args, { cwd: TEST_DIR, stdio: "inherit" });
  testProcess.on("close", function (code) {
    done();
  });
}
gulp.task("default", function (done) {
  console.log("Available tasks:");
  const tasks = Object.keys(gulp.registry().tasks());
  for (const taskName of tasks.sort()) {
    if (taskName.endsWith("-pre")) {
      continue;
    }
    console.log("  " + taskName);
  }
  done();
});
function createBuildNumber(done) {
  console.log();
  console.log("### Getting extension build number");
  exec(
    "git log --format=oneline " + config.baseVersion + "..",
    function (err, stdout, stderr) {
      let buildNumber = 0;
      if (!err) {
        
        buildNumber = stdout ? stdout.match(/\n/g).length : 0;
      } else {