ClickHouse Client and Local Default to Multi-Query Mode

clickhouse-client and clickhouse-local now default to multi-query mode (instead single-query mode). As an example, clickhouse-client -q "SELECT 1; SELECT 2" now works, whereas users previously had to add --multiquery (or -n). The --multiquery/-n switch became obsolete. INSERT queries in multi-query statements are treated specially based on their FORMAT clause: If the FORMAT is VALUES (the most common case), the end of the INSERT statement is represented by a trailing semicolon ; at the end of the query. For all other FORMATs (e.g. CSV or JSONEachRow), the end of the INSERT statement is represented by two newlines \n\n at the end of the query. #63898 (FFish).