DOCS: Remove git workflow info from contributing document
DOCS: Remove git workflow info from contributing document

This will now be centralised in the API documentation

doubtfire-lms/doubtfire-web,final-year-project/doubtfire-web,doubtfire-lms/doubtfire-web,final-year-project/doubtfire-web,doubtfire-lms/doubtfire-web,alexcu/doubtfire-web,doubtfire-lms/doubtfire-web,alexcu/doubtfire-web