R1:de01f3e2e08e

Add Maniphest Task email creator to CCs

Summary: Fixes T9369.

Test Plan:
- Sent a mail with Mail.app to `bugs@local.phacility.com`.
- Used "View Raw Mail", copy-pasted it into `mail.txt` on disk.
- Ran `cat mail.txt | ./scripts/mail/manage_mail.php --process-duplicates`.
- Saw task get created and me get added as CC.
- Changed "To" to include another user, ran command again, saw task get created and other user get added as CC.

Reviewers: chad

Reviewed By: chad

Subscribers: Korvin

Maniphest…