lint(lazy_io): unify class lazy_resume_on

Author: Codesire-Deng

include/co_context/detail/lazy_io_awaiter.hpp

@@ -898,7 +898,7 @@ struct lazy_who_am_i {
 
 using lazy_forget = std::suspend_always;
 
-struct lazy_resume_on {
+class lazy_resume_on {
   public:
     static constexpr bool await_ready() noexcept { return false; }