Excessive docker cache build up on the TRSS machine

[Haroon-Khel]

On the trss machine, 20.90.182.165:

sdc                       8:32   0   128G  0 disk 
└─sdc1                    8:33   0   128G  0 part 
  ├─trss--vg-trss--data 253:0    0    60G  0 lvm  /home/jenkins/trss
  ├─trss--vg-docker     253:1    0    50G  0 lvm  /var/lib/docker

trss--vg-trss--data is where mongo stores its data
trss--vg-docker is for docker related things.

it looks like alot of docker cache is building up on the machine. I cleared 21G of cache today but running docker system prune (after shutting the trss server down for a bit). I also added an extra 20G to trss--vg-docker.

Needs to be investigated why this much build up occurs