REPORT-112857 fix: 改下isDir的写法

src/main/java/com/fanruan/fs/s3/repository/core/S3ResourceRepository.java

@@ -412,17 +412,7 @@ public class S3ResourceRepository extends BaseResourceRepository {
 
     @Override
     public boolean isDirectory(String path) {
-        if (path.endsWith(DELIMITER)) {
-            return exist(path);
-        } else {
-            ObjectListing listing = s3.listObjects(bucket, path);
-            List<S3ObjectSummary> objectSummaries = listing.getObjectSummaries();
-            if (objectSummaries.isEmpty()) {
-                return false;
-            }
-            String dirFormat = path + DELIMITER;
-            return objectSummaries.stream().anyMatch(s3ObjectSummary -> StringUtils.equals(s3ObjectSummary.getKey(), dirFormat));
-        }
+        return dirExist(path);
     }
 
     @Override