system_tables.md: update system tables of plugins

Summary

• system_tables.md: update system tables of plugins

Address changes from picodata!1000 (merged)

Version: Picodata 24.4.0-32-g7f3221f6 (picodata@7f3221f6)

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• Cherry-pick to: none
• Staging:
  • https://docs.binary.picodata.io/picodata/asabirov_update_plugins_system_tables/architecture/system_tables/#_pico_plugin
  • https://docs.binary.picodata.io/picodata/asabirov_update_plugins_system_tables/architecture/system_tables/#_pico_service