[Node Daemon ] Updating the outdated bitcoind.service.

Summary: Provide a template for the eCash Node Daemon Setup Guide

Test Plan: The tests have been conducted on three different VPSs, each running Ubuntu, and each provided by a different service provider.

Reviewers: Fabien, O1 Bitcoin ABC, #bitcoin_abc, Mengerian

Reviewed By: Fabien, O1 Bitcoin ABC, #bitcoin_abc, Mengerian

Subscribers: Mengerian, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D14899