Copy to /etc/cron.d/pihole-update
You cannot edit the existing /etc/cron.d/pihole
script as it will over-write itself on first update.
Why this isn't shipped with PiHole itself, is just fucking beyond me.
I for one LOVE SSH'ing into all my IoT devices every week to run random commands just to keep them up to date.
All hail our PHP overlords.