Fix regex for affirm parser

[earlduque]

The regex flag on the header is incorrect
!affirm, !affirm @user
should be just !affirm, otherwise it's looking for the exact literal string "!affirm, !affirm @user"

dropping the !affirm @user part seems fine too because the parser doesn't seem to be trying to do anything with the username anyways

[ajcooper72]

I'll fix this up now.

[SapphicFire]

Closing as @ajcooper72 has addressed