Add info about how to edit message in DM'd help

[Namaskar-1F64F]

Is your feature request related to a problem? Please describe.
More info about how stoodbot updates would give users more confidence on how it will work and output.

Describe the solution you'd like
A help command or reminders when someone posts a lot of updates, "remember you can edit your previous messages and I'll send the updated version" or a way to preview and erase the update to start over.

Describe alternatives you've considered
Telling the person myself how it works. That doesn't solve the problem for everyone and makes me do extra work.

Additional context