fix corner cases for check free space size before download, fix #878

Author: Slach

ChangeLog.md

@@ -1,3 +1,7 @@
+# v2.6.11
+BUG FIXES
+- fix another corner cases for check free space size before download, fix [878](https://github.com/Altinity/clickhouse-backup/issues/878)
+
 # v2.6.10
 BUG FIXES
 - fix corner cases for `restore_schema_on_cluster: true` and `<user_defined_zookeeper_path>`, fix [1123](https://github.com/Altinity/clickhouse-backup/issues/1123)