chore: replace async-channel with already exist flume dep

Signed-off-by: tison <wander4096@gmail.com>

Author: tisonkun

foyer-storage/Cargo.toml

@@ -18,7 +18,6 @@ allocator-api2 = "0.2"
 anyhow = "1.0"
 # TODO(MrCroxx): use `array_chunks` after `#![feature(array_chunks)]` is stable.
 array-util = "1"
-async-channel = "2"
 auto_enums = { version = "0.8", features = ["futures03"] }
 bincode = "1"
 bytes = "1"

foyer-storage/src/region.rs

@@ -24,7 +24,7 @@ use std::{
     task::{Context, Poll},
 };
 
-use async_channel::{Receiver, Sender};
+use flume::{Receiver, Sender};
 use foyer_common::{countdown::Countdown, metrics::Metrics};
 use futures_core::future::BoxFuture;
 use futures_util::{future::Shared, FutureExt};
@@ -154,7 +154,7 @@ impl RegionManager {
                 stats: Arc::new(RegionStats::default()),
             })
             .collect_vec();
-        let (clean_region_tx, clean_region_rx) = async_channel::unbounded();
+        let (clean_region_tx, clean_region_rx) = flume::unbounded();
 
         metrics.storage_region_total.absolute(device.regions() as _);
         metrics.storage_region_size_bytes.absolute(device.region_size() as _);