Fix doc blocks in io_poll.stub.php

/* */ comments are ignored by the stub parser.

Author: iluuu1994

ext/standard/io_poll.stub.php

@@ -39,7 +39,7 @@ interface Handle
     {
     }
 
-    /*
+    /**
      * @strict-properties
      * @not-serializable
      */
@@ -70,7 +70,7 @@ public function modifyData(mixed $data): void {}
         public function remove(): void {}
     }
 
-    /*
+    /**
      * @strict-properties
      * @not-serializable
      */
@@ -145,7 +145,7 @@ class InvalidHandleException extends PollException {}
 }
 
 namespace {
-    /*
+    /**
      * @strict-properties
      * @not-serializable
      */