better error message when --single is not the first arg to postgres executable

2024-12-04 21:26:27 Nathan Bossart (bossartn) Closed in commitfest 2025-01 with status: Committed 2024-12-02 15:38:13 Nathan Bossart (bossartn) Closed in commitfest 2024-11 with status: Moved to next CF 2024-10-03 20:51:43 Nathan Bossart (bossartn) Closed in commitfest 2024-09 with status: Moved to next CF 2024-08-27 15:13:48 Nathan Bossart (bossartn) Changed authors to Nathan Bossart (bossartn), Greg Sabino Mullane (greg) 2024-08-27 15:13:39 Nathan Bossart (bossartn) New status: Ready for Committer 2024-08-27 15:13:37 Nathan Bossart (bossartn) Added bossartn as committer 2024-08-01 02:13:23 Corey Huinker (coreyh) Closed in commitfest 2024-07 with status: Moved to next CF 2024-06-18 19:53:58 Nathan Bossart (bossartn) Changed reviewers to Nathan Bossart (bossartn) 2024-06-18 19:53:58 Nathan Bossart (bossartn) Changed authors to Greg Sabino Mullane (greg) 2024-06-18 19:53:58 Nathan Bossart (bossartn) Changed targetversion to 18 2024-06-18 19:53:45 Nathan Bossart (bossartn) Attached mail thread CAKAnmmJkZtZAiSryho=gYpbvC7H-HNjEDAh16F3SoC9LPu8rqQ@mail.gmail.com 2024-06-18 19:53:45 Nathan Bossart (bossartn) Created patch record