Fix return value error and Remove useless code (#655)

* Fix return value error

* Remove useless code

Author: sy-records

src/Commands/StartRoadRunnerCommand.php

@@ -171,7 +171,7 @@ protected function maxExecutionTime()
     /**
      * Get the RPC IP address the server should be available on.
      *
-     * @return int
+     * @return string
      */
     protected function rpcHost()
     {

src/Swoole/SwooleClient.php

@@ -140,7 +140,7 @@ public function serveStaticFile(Request $request, RequestContext $context): void
         $publicPath = $context->publicPath;
         $octaneConfig = $context->octaneConfig ?? [];
 
-        if (! empty($octaneConfig['static_file_headers'] ?? [])) {
+        if (! empty($octaneConfig['static_file_headers'])) {
             foreach ($octaneConfig['static_file_headers'] as $pattern => $headers) {
                 if ($request->is($pattern)) {
                     foreach ($headers as $name => $value) {