engine: Implement COPY INTO

[osipovartem]

https://docs.snowflake.com/en/sql-reference/sql/copy-into-table

COPY INTO SNOWPLOW_ICEBERG.SNOWPLOW_WEB.SAMPLE_EVENTS_WEB_BASE FROM @~/snowplow_web_sample_stage
FILE_FORMAT = (TYPE=CSV field_delimiter=',' skip_header=1 FIELD_OPTIONALLY_ENCLOSED_BY='"');