Add infraction history update command

[pushiscool]

Added Task 8.

Changes:

• Adds indexes to /warnings embeds
• Shows each infraction as Refactor code #1, Let deletion of question messages happen, and perm the ping/delete so only helpers and the question asker can do it #2, Add macro system #3, etc.
• Adds /update for moderators
• Allows mods to update an infraction reason by index
• Allows mods to delete an infraction by index
• Allows mods to add a note/context to an infraction by index
• Notes show in /warnings
• Keeps legacy infraction display working, including old mute reason, duration, date, and moderator
• Adds database helper methods for updating, deleting, and adding notes to infractions
• Adds tests for update/delete/note behavior