Add tree package to Dockerfile to enhance file system navigation

[ThomasSanson]

Hello Team,

I've identified a small issue in our Dockerfile that could be improved. Currently, the tree package is not included in our Docker image. This package could greatly enhance our file system navigation when we're troubleshooting or just exploring our Docker container.

By adding tree to our Dockerfile, we'll be able to generate an ASCII graphic of a directory structure which can aid us in understanding our file system hierarchy and layout better.

Here is the proposed change in Dockerfile:

RUN apt-get install -y tree

I believe this is a small change that can make our Docker image more user-friendly and efficient. I would appreciate your thoughts on this and if there are no objections, I will proceed with this update.