Create Contributing.md file

[tungbq]

Quick task as below:

• Copy content from latest contributing file from main branch of tungbq/devops-basic repository: https://github.com/tungbq/devops-basic/blob/main/CONTRIBUTING.md
• Create new CONTRIBUTING.md under this repository and paste above content
• Check and update the content and replace all text, URLs, hyperlinks devops-basic by find-github-issue (This repo)
• Create PR and done!