Fix typo: Wroker -> Worker (#2597)

docs/setup.en.md

@@ -54,7 +54,7 @@ Please visit https://www.google.com/recaptcha/intro/ and generate keys.
 
 *(optional)* Generating VAPID keys
 ----------------------------------------------------------------
-If you want to enable ServiceWroker, you need to generate VAPID keys:
+If you want to enable ServiceWorker, you need to generate VAPID keys:
 Unless you have set your global node_modules location elsewhere, you need to run this in root.
 
 ``` shell

src/server/web/index.ts

@@ -63,7 +63,7 @@ router.get('/apple-touch-icon.png', async ctx => {
 	});
 });
 
-// ServiceWroker
+// ServiceWorker
 router.get(/^\/sw\.(.+?)\.js$/, async ctx => {
 	await send(ctx, `/assets/sw.${ctx.params[0]}.js`, {
 		root: client