Enhancement request: don't refer to initdb from git repository

**Is your enhancement request related to a problem? Please describe.**

I wanted to have a simple Docker setup for local use that wasn't intended for development but for using DejaCode. Therefore I had no need for building a Docker container or having a build environment. I was looking for a simple Docker Compose file with the necessary containers that exist.

I was surprised by the explicit volume mount of the Postgresql database seed:
https://github.com/aboutcode-org/dejacode/blob/c3399c8056d05eb0fbff13604ae4b3e8229a3bc0/compose.yml#L12

In this way the Docker compose files have a dependency on this git repository. This mount is present in all Docker compose files in this repository.

In the setup I came up with, I finally added the database seed to get it running. https://codeberg.org/nicorikken/aboutcode-locally

I'm surprised of the additional complexity of managing this database seed in a container-based setup. I would have expected a more implicit setup.

**What are the benefits of the requested enhancement?**

If the database seed would have been managed from within the built containers, the docker-compose setup would be simpler and would need nothing more than a `docker-compose.yml` file or maybe an nginx config and environment file if they aren't embedded into the compose file.

**Describe the solution you would like**

I would expect Dejacode to manage the database seed. I see a few options:

1. Ship the database seed within the container. This risks the database seed having become outdated.
2. Download the database seed at boot. This risks the download being blocked by the network. A manual install could be documented.

**Additional notes**

_None_