* Upgrade postgres-backup-s3 to psql 17
The upstream `go-crond` repo now uses `main` as it's base branch, so the
tag name changed.
* postgres-backup-s3: honor extra opts in pg_dumpall
The setting was being used in `psql`, but not when POSTGRES_BACKUP_ALL
is set.
* Fix: postgres-backup-s3 crontab syntax
It was yielding an error "user lookup failed: user: unknown user
/bin/sh"