Remove legacy non-existing monaco worker route (#6995)

_No functional change intended_

According to
7ce90a3388
and
0d0a52e249
the route was added a very long time ago (4-5 years) to support compat
for workers downloaded to the user's browsers.

In addition to this being very long ago to the point that the chance of
anybody having an old CE worker being extremely low, those files no
longer exist.

We tag our webpack bundles with a "magic version" (current .v53.) to
force the browsers to re-fetch the bundles for major changes. That means
that if somebody had `editor.v10.worker.[hash].js` from years ago, that
file won't even be in our current bundle, and has to be in their
browser's cache (unlikely because it's so old, but even then their
browser wouldn't hit this route due to cache)

app.ts

@@ -749,41 +749,6 @@ async function main() {
     // Based on combined format, but: GDPR compliant IP, no timestamp & no unused fields for our usecase
     const morganFormat = isDevMode() ? 'dev' : ':gdpr_ip ":method :url" :status';
 
-    /*
-     * This is a workaround to make cross origin monaco web workers function
-     * in spite of the monaco webpack plugin hijacking the MonacoEnvironment global.
-     *
-     * see https://github.com/microsoft/monaco-editor-webpack-plugin/issues/42
-     *
-     * This workaround wouldn't be so bad, if it didn't _also_ rely on *another* bug to
-     * actually work.
-     *
-     * The webpack plugin incorrectly uses
-     *     window.__webpack_public_path__
-     * when it should use
-     *     __webpack_public_path__
-     *
-     * see https://github.com/microsoft/monaco-editor-webpack-plugin/pull/63
-     *
-     * We can leave __webpack_public_path__ with the correct value, which lets runtime chunk
-     * loading continue to function correctly.
-     *
-     * We can then set window.__webpack_public_path__ to the below handler, which lets us
-     * fabricate a worker on the fly.
-     *
-     * This is bad and I feel bad.
-     *
-     * This should no longer be needed, but is left here for safety because people with
-     * workers already installed from this url may still try to hit this page for some time
-     *
-     * TODO: remove this route in the future now that it is not needed
-     */
-    router.get('/workers/:worker', (req, res) => {
-        staticHeaders(res);
-        res.set('Content-Type', 'application/javascript');
-        res.end(`importScripts('${urljoin(staticRoot, req.params.worker)}');`);
-    });
-
     router
         .use(
             morgan(morganFormat, {