Fix docker entrypoint failure when host user is 'ubuntu'

[jo-fra]

Problem

When the host username is ubuntu, docker/run_docker.sh fails at container startup with:

userdel: user 'ubuntu' does not exist
useradd: group 'ubuntu' does not exist

Root Cause

In entrypoint.sh, groupadd --force runs before userdel ubuntu. Since the base image already has a ubuntu user/group, the sequence is:

1. groupadd --force — group ubuntu already exists, no-op
2. userdel ubuntu — deletes the user and its primary group
3. useradd --gid ubuntu — fails because the group was removed in step 2

Fix

Move userdel calls before groupadd, so the group is always (re)created after any prior user/group removal.