[BUG] Don't starve together... Cave Server won't use proper ports.

## User Story

Trying simply to start a 'Caves' server to compliment it's "Overworld" counterpart.

## Basic info

* **Distro:** [debian]
* **Game:** [Don't Starve Together]
* **Command:** [./dstserver-2 st]
** [LinuxGSM version: v21.2.3]

## Further Information

Overworld server is running properly using the default installed config file:
/home/dsttesting/.klei/DoNotStarveTogether/Cluster_1/Master/server.ini

I issued the ./linuxgsm.sh install and the subsequent ./dsterver-2 was generated.

However ./dstserver-2 is also reading
/home/dsttesting/.klei/DoNotStarveTogether/Cluster_1/Master/server.ini

It should be reading :
/home/dsttesting/.klei/DoNotStarveTogether/Cluster_1/Caves/server.ini

I have tried to over-ride the port by using the instance.cfg file. No matter what commands I put in there they are all "Not Found"

making the ./dstserver-2 read the proper config file. would be the optimum solution.

## To Reproduce

Steps to reproduce the behaviour:
1. Install DST Server
2. Configure ports for the basic install.
3. then run ./linuxgsm.sh install to generate the ./dstserver-2
4. Modify ports launch server. the server will only read the : /home/dsttesting/.klei/DoNotStarveTogether/Cluster_1/Master/server.ini
5. To get the multi server config files proper I followed this : https://docs.linuxgsm.com/game-servers/dont-starve-together

## Expected behaviour
That the main "Overworld Server" starts using it's config files.
and that the Caves Server starts and uses It's proper config files as defined.

Thank you for your time and any assistance you may have to offer..