This issue happens on production of one user that enabled Sentry:

![Screenshot_20210303_002028](https://user-images.githubusercontent.com/18581488/109716945-7f9a1200-7bb6-11eb-8cf4-1080ad535d18.png)

Build id: 49938CCB63EE2A4E16CF0528307EE15F08469219.
{
            return name;
        }
        Chunk generate() override
        {
            if (!reader)
                return {};
            if (!initialized)
                reader->readPrefix();
            initialized = true;
            if (auto block = reader->read())
                return Chunk(block.getColumns(), block.rows());
            reader->readSuffix();
            reader.reset();
            return {};
        }
    private:
        String name;
        std::unique_ptr<ReadBuffer> read_buf;
        BlockInputStreamPtr reader;
        bool initialized = false;
    };
}
StorageURLBlockOutputStream::StorageURLBlockOutputStream(const Poco::URI & uri,