Retention policy does not delete physical files on disk

Description:

When enabling and configuring the retention policy, files are pruned from the chats, but the files are not deleted physically from the disk drive mounted mapped to the docker container

Steps to reproduce:

1. Apply retention policy for pruning files and messages

Expected behavior:

Files are pruned both from the chats, channels AND from the filesystem on which the files are stored

Actual behavior:

Files are pruned from chats but persist on the filesystem storage

Server Setup Information:

• Version of Rocket.Chat Server: 3.6.1, also tested on 4.6.1
• Operating System: Centos 7.8
• Deployment Method: Docker
• Number of Running Instances: 1
• DB Replicaset Oplog: enabled
• MongoDB Version: 4.0.19 for Rocket 3.6.1; 5.0.6 for rocket 4.6.1
• Storage type: Filesystem storage

Client Setup Information

• Desktop App or Browser Version: Chrome , Firefox, Desktop app 3.7.x
• Operating System:

Additional context

For these installation, the storage method used is filesystem storage; a dedicated disk on the host machine is mapped to the rocket docker container.

Start by reproducing the retention-policy pruning with filesystem storage on a Docker deployment, using the versions and storage setup described in the issue. Trace the retention job and filesystem-storage path, then verify that pruning removes files from chats and channels and from the host-mounted filesystem.