feat: implement the 'signedoffby' module

[rolasotelo]

PR Description: New Module - Commit Footer Sign-off

Overview

This PR introduces the signedoffby module, designed to automate the inclusion of a "Signed-off-by" token in the footer of each commit message. This addition ensures that all commits carry an acknowledgment from the author, enhancing the integrity and traceability of contributions. Plus a CHANGELOG.md file was added (idea is to follow https://keepachangelog.com/en/1.1.0/).

Implementation Details

• Module Name: signedoffby
• Key Feature: Automatic appending of Signed-off-by to the commit footer.
• Activation: Configurable via module settings; no user input required during the commit process.

Changes Made

1. New Module Implementation: Created signedoffby.go in pkg/modules/signedoffby, implementing the module logic.

2. Post-Processing Logic:

   • Utilized os/exec to fetch the author's name and email from Git configuration.
   • Formatted and appended the "Signed-off-by" token to the commit footer.

[rolasotelo]

Task linked: CU-869430y06 feat: implement signed-off-by module