As title, remove the GCS/S3 staging methods. There isn't much usage so we can remove this. Internal Staging is also recommended by Snowflake, so using that is both cheaper and faster. Co-authored-by: davinchia <davinchia@users.noreply.github.com> Co-authored-by: Evan Tahler <evan@airbyte.io> Co-authored-by: Pedro S. Lopez <pedroslopez@me.com>