refactor: use entry.Size if valid value

Minio works best when it knows the object size prior to upload so if we
have that information we should use it.

The fallback is what we had previously `-1`.

See: https://github.com/minio/minio-go/blob/66ba593a19a7a9d1c302ff2b5c05bf17d73a0d1f/api-put-object.go#L279-L280

storage/minio.go

@@ -188,7 +188,11 @@ func (s *StorageMinio) PutObject(bucket Bucket, fpath string, contents io.Reader
 		opts.UserMetadata["Mtime"] = fmt.Sprint(entry.Mtime)
 	}
 
-	info, err := s.Client.PutObject(context.TODO(), bucket.Name, fpath, contents, -1, opts)
+	var objSize int64 = -1
+	if entry.Size > 0 {
+		objSize = entry.Size
+	}
+	info, err := s.Client.PutObject(context.TODO(), bucket.Name, fpath, contents, objSize, opts)
 
 	if err != nil {
 		return "", 0, err