message: fix compilation error for feature=local-dns-relay
diff: @@ -20,7 +20,7 @@ use log::{log_enabled, warn};
  #[cfg(any(feature = "local-dns-relay", feature = "acl-check-cache"))]
  use lru_time_cache::LruCache;
  use spin::Mutex as SpinMutex;
  -#[cfg(feature = "acl-check-cache")]
  +#[cfg(any(feature = "local-dns-relay", feature = "acl-check-cache"))]
  use tokio::sync::Mutex as AsyncMutex;
  #[cfg(feature = "trust-dns")]
  use trust_dns_resolver::TokioAsyncResolver;
  