Fix file count leak

commit_hash:b472de3acfa4f30ba4b3e630721a38a577c35c85

Author: antoniox

yql/essentials/core/file_storage/storage.cpp

@@ -305,7 +305,7 @@ class TStorage::TImpl: public TIntrusiveListItem<TImpl> {
         const bool result = NFs::Remove(storageFile);
 
         if (result || !storageFile.Exists()) {
-            ++CurrentFiles_;
+            --CurrentFiles_;
             CurrentSize_ -= prevFileSize;
         }