volume server: remote tier volumes only soft delete in local index

fix https://github.com/seaweedfs/seaweedfs/issues/3889

weed/storage/volume_write.go

@@ -213,14 +213,18 @@ func (v *Volume) doDeleteRequest(n *needle.Needle) (Size, error) {
 	nv, ok := v.nm.Get(n.Id)
 	// fmt.Println("key", n.Id, "volume offset", nv.Offset, "data_size", n.Size, "cached size", nv.Size)
 	if ok && nv.Size.IsValid() {
+		var offset uint64
+		var err error
+		if !v.hasRemoteFile {
 			size := nv.Size
 			n.Data = nil
 			n.AppendAtNs = uint64(time.Now().UnixNano())
-		offset, _, _, err := n.Append(v.DataBackend, v.Version())
+			offset, _, _, err = n.Append(v.DataBackend, v.Version())
 			v.checkReadWriteError(err)
 			if err != nil {
 				return size, err
 			}
+		}
 		v.lastAppendAtNs = n.AppendAtNs
 		if err = v.nm.Delete(n.Id, ToOffset(int64(offset))); err != nil {
 			return size, err