Wrap service inside systemd unit + build pipeline (GitLab CLI -> .deb -> GitLab Package Registry)

This branch is build upon changes of !1 (commits).

Part 1: systemd

This update wraps the executable into a systemd unit. This systemd service works along with another service we have i.e. nomad-client.service. Benefits?

• This enables to start the service as soon as the system starts.
• Enables logging management with journalctl.

Part 2: CI Pipeline

As Ubuntu is the first distro we are going to support, the final artifact we get after pushing changes to VCS is a .deb file.

• Architectures we plan to support: arm64, amd64
• Ubuntu version we plan to support: 18.04, 20.04, 22.04

Although attempt has been made to fulfil above mentioned point, the finding has been posted in the linked ticket.

Closes #21 (closed)