File ownership

If user is running Docker rootless, this is how user ID is mapped

```mermaid
flowchart TB
subgraph container[rootless container]
container-root[root UID=0]
container-pgadmin4[pgadmin4 UID=5050]
end

subgraph host
host-root[root UID=0]
alice[alice UID=1002]
bob[bob UID=1003]
host-pgadmin4[pgadmin4 UID=105050]
end

bob-->container-root
host-pgadmin4-->container-pgadmin4
```

This means that user will not have problem with files being owned by `root`.