fix: clippy

ecstore/src/client/utils.rs

@@ -1,5 +1,5 @@
 use lazy_static::lazy_static;
-use std::collections::{HashMap, HashSet};
+use std::collections::HashMap;
 
 use s3s::header::X_AMZ_STORAGE_CLASS;
 
@@ -75,4 +75,4 @@ pub fn is_rustfs_header(header_key: &str) -> bool {
 
 pub fn is_minio_header(header_key: &str) -> bool {
     header_key.to_lowercase().starts_with("x-minio-")
-}
+}