The last line in `data` section of the output is always empty. 

```
# clickhouse-client
ClickHouse client version 20.5.2.7 (official build).
Connecting to localhost:9001 as user default.
Connected to ClickHouse server version 20.5.2 revision 54435.

sas-vrxctd96rqw5lw25.db.yandex.net :) select 1 format JSON

SELECT 1
FORMAT JSON

{
	"meta":
	[
		{
			"name": "1",
			"type": "UInt8"
		}
	],

	"data":
	[
		{
			"1": 1

	],

	"rows": 1,

	"statistics":
	{
		"elapsed": 0.00019223,
		"rows_read": 1,
		"bytes_read": 1
	}
}

```

The issue appears only in interactive mode. In non-interactive mode clickhouse-client produces the correct output:

```
# clickhouse-client -q 'select 1 format JSON'
{
	"meta":
	[
		{
			"name": "1",
			"type": "UInt8"
		}
	],

	"data":
	[
		{
			"1": 1
		}
	],

	"rows": 1,

	"statistics":
	{
		"elapsed": 0.000220845,
		"rows_read": 1,
		"bytes_read": 1
	}
}
``` 

std::optional<WriteBufferFromFile> out_file_buf
    BlockOutputStreamPtr block_out_stream
    /// The user could specify special file for server logs (stderr by default)
    std::unique_ptr<WriteBuffer> out_logs_buf
    String server_logs_file
    BlockOutputStreamPtr logs_out_stream
    String home_path
    String current_profile
    String prompt_by_server_display_name
    /// Path to a file conining command history.
    String history_file
    /// Ho many ros have been read or ritten.
    size_t processed_ros = 0
    /// Parsed query. Is used to determine some settings (e.g. format, output file).
    ASTPtr parsed_query
    /// The last exception that as received from the server. Is used for the return code in batch mode.
    std::unique_ptr<Exception> last_exception_received_from_server
    /// If the last query resulted in exception.
    bool received_exception_from_server = false
    int expected_server_error = 0
    int expected_client_error = 0
    int actual_server_error = 0
    int actual_client_error = 0
    UInt64 server_revision = 0
    String server_version
    String server_display_name
    Stopatch atch
    /// The server periodilly sends information about ho much da as read since last time.
    Progress progress
    bool sho_progress_bar = false