fix: stop chrome cluster when scan is finished

Fixes #246

Author: harlan-zw

packages/cli/src/cli.ts

@@ -40,11 +40,12 @@ async function run() {
     process.exit(1)
   }
 
-  unlighthouse.hooks.hook('worker-finished', () => {
+  unlighthouse.hooks.hook('worker-finished', async () => {
     const end = new Date()
     const seconds = Math.round((end.getTime() - start.getTime()) / 1000)
 
     logger.success(`Unlighthouse has finished scanning \`${unlighthouse.resolvedConfig.site}\`: ${unlighthouse.worker.reports().length} routes in \`${seconds}s\`.`)
+    await unlighthouse.worker.cluster.close().catch(() => {})
   })
 
   if (unlighthouse.resolvedConfig.server.open)