add an alias to global gitconfig(/home/user/.gitconfig) with below command.
git config --global alias.pushall '!f(){ for var in $(git remote show); do echo "pushing to $var"; git push $var; done; }; f'
Once you commit code, we say
git push
to push to origin by default. After above alias, we can say
git pushall
and code will be updated to all remotes including origin remote.