(fleet/grafana-dashboards) update Deliverator Summary dash

changes:

- add [new] metrics:
    - s3nd_upload_valid_requests_total
    - s3nd_s3_tcp_conn_pace_bytes
    - s3nd_s3_tcp_conn_pace_max_bytes
    - s3nd_s3_tcp_conn_active
    - s3nd_s3_tcp_conn_closed_total
- add $scrape_interval & $resolution vars
- fix tcp_info_bytes_retrans plot using wrong metric
- reduced min interval to 100ms for all plots
- set most plots to symlog scale

Author: jhoblitt