Force local forked repo to be exactly like upstream

sync_with_upstream.md

WARNING: This will override any local custom changes made to the repository and replace it's contents to be exactly like the upstream repo, use git remote -v to check the origin and upstream repos, the origin will be replaced to be identical with the upstream.

git fetch upstream
git checkout master
git reset --hard upstream/master  
git push origin master --force

Initially to set the upstream the following command was used:

git remote add upstream https://github.com/$some_user/$some_repo