Improved README.md with detailed build and contribution instructions

[jigarvyasidea]

• Updated README.md to include more detailed instructions for building the Odoo documentation locally.
• Added optional setup details for building Python docstrings.
• Clarified additional make commands and how to view the generated HTML documentation.
• Enhanced the section on contributing, including links to the Introduction Guide and issue tracker.
• Provided resources for learning more about Odoo, such as the official eLearning platform and Scale-up business game.

[robodoo]

[jigarvyasidea]

This pull request improves the existing README.md file by adding clearer and more detailed instructions for building the Odoo documentation locally. It also includes guidelines for contributing, optional setup for Python docstrings, and additional resources for learning about Odoo.

Please review the updates, and let me know if any further changes are required. Looking forward to your feedback.

[jigarvyasidea]

Hi Robodoo,

I noticed your message regarding contributions, and I would like to get involved. Could you please clarify which repository currently requires contributions? I want to ensure that my efforts are directed where they are most needed.