[BUG] monitor starts server while it's backing up causing duplicate instances

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## User Story

I have a LGSM PaperMC server running. I have an LGSM monitor cron running every 5 minutes. I'm not even sure if that's necessary but I've disabled it now due to this issue anyway. I've had it running for months and had no issues. The server restarts once a day automatically by running a LGSM backup. Suddenly today I realize it has caused a server to attempt to run twice at once causing one instance to crash due to a lock file being found and one instance to be inaccessible to any LGSM commands. For example trying to stop the server says it's not running, trying to start a new one says it's already running, and there were no tmux sessions available to connect to either. There was a java process trying to run the server. I had to kill it to shut it down.

## Basic info

* **Distro:** [Ubuntu 22.04.1 LTS]
* **Game:** [PaperMC]
* **Command:** [Monitor, Backup]
* **LinuxGSM version:** [v22.1.0]

## Further Information

Monitor starts a server that is currently backing up, possibly after it has finished backing up but has begun but not completed starting itself again.

The server runs `~/pmcserver backup` to backup and restart itself.

## To Reproduce

Steps to reproduce the behaviour:
1. Backup
2. Run monitor at just the right time.

## Expected behaviour

Should backup and start the server again without trying to monitor it to restart it causing duplicate instances.

Thank you!