[Bug]: pzserver BACKUP incomplete

### User story

As a LGSM admin I want the backup functionality to properly capture all pertinent files to accomplish, if required, a successful restore

### Game

PZSERVER

### Linux distro

Ubuntu 22.04

### Command

command: backup

### Further information

Testing a new install [compose file] as I'm migrating from LinuxGSM-Docker. Backup command issued & finishes (successfully) but output file is incomplete.

Backup file only contains data from container's '/APP' location, no actual game server files

[pzserver-2023-11-19-093415.tar.gz](https://github.com/GameServerManagers/LinuxGSM/files/13403564/pzserver-2023-11-19-093415.tar.gz)

### Relevant log output

```shell
Nov 19 09:33:56.732 pzserver: MONITOR: INFO: Query bypassed: pzserver started less than 10 minutes ago
Nov 19 09:33:56.737 pzserver: MONITOR: INFO: Server started: Sun Nov 19 09:32:17 AM EST 2023
Nov 19 09:33:56.739 pzserver: MONITOR: INFO: Current time: Sun Nov 19 09:33:56 AM EST 2023
Nov 19 09:33:56.745 pzserver: MONITOR: INFO: LinuxGSM version: v23.6.2
Nov 19 09:33:56.746 pzserver: MONITOR: PASS: core_exit.sh exiting with code: 0
Nov 19 09:34:16.444 pzserver: BACKUP: INFO: Starting backup
Nov 19 09:34:16.547 pzserver: BACKUP: INFO: No previous backups found
Nov 19 09:34:16.657 pzserver: BACKUP: WARN: pzserver is currently running
Nov 19 09:34:16.659 pzserver: BACKUP: WARN: Although unlikely; creating a backup while pzserver is running might corrupt the backup
Nov 19 09:34:16.663 pzserver: BACKUP: INFO: Backup lockfile generated
Nov 19 09:34:16.665 pzserver: BACKUP: INFO: /app/lgsm/lock/backup.lock
Nov 19 09:34:16.768 pzserver: BACKUP: INFO: A total of 5.1G will be compressed: /data/backup/pzserver-2023-11-19-093415.tar.gz
Nov 19 09:34:17.271 pzserver: BACKUP: INFO: Backup 5.1G pzserver-2023-11-19-093415.tar.gz, in progress
Nov 19 09:34:17.519 pzserver: BACKUP: PASS: Backup created: pzserver-2023-11-19-093415.tar.gz, total size 136K
Nov 19 09:34:17.524 pzserver: BACKUP: INFO: Sending alert: pzserver has been backed up
Nov 19 09:34:19.551 pzserver: BACKUP: PASS: Sending Discord alert
Nov 19 09:34:19.906 pzserver: BACKUP: INFO: LinuxGSM version: v23.6.2
Nov 19 09:34:19.907 pzserver: BACKUP: WARN: core_exit.sh exiting with code: 3
```

### Steps to reproduce

1. Console into container
2. Issue './*server backup'
3. Check log output & note discrepancy of expected file size vs. final
4. Verify same in backup file produced
5. Redirect BACKUP folder (either via LGSM Config or docker-compose VOLUMES), retest: same result
[pzserver-script.log](https://github.com/GameServerManagers/LinuxGSM/files/13403574/pzserver-script.log)