add git repository heroku code example

Example 1: heroku and github on termi

$ heroku git:remote -a thawing-inlet-61413
set git remote heroku to https://git.heroku.com/thawing-inlet-61413.git

Example 2: set git remote heroku to https://git.heroku.com/resume-projects.git

$ git push heroku testbranch:master