Add more SQL examples how to query database

[MRIIOT]

example:

SELECT
  substring(path,'$device/(.*)') as attribute,
  time,
  value,
  lower(units) as units
FROM history_all
WHERE
  path IN ('$device/Availability', '$device/LoadCondition', '$device/Message', '$device/FunctionalMode',
  '$device/SystemCondition', '$device/Controller/EmergencyStop', '$device/Axes/Rotary[C]/RotaryMode')

  and $__timeFilter("time")
order by time desc
limit 200

[MRIIOT]

@bburns Proposed tasks have no assignees.

[tukusejssirs]

@MRIIOT, we might want to configure GitHub Action to auto-remove all assignees when an issue is in proposed in the project.