// For permanently stop git from asking credentials
$ git config credential.helper store
$ git push https://github.com/repo.git

Username for 'https://github.com': 
Password for 'https://USERNAME@github.com': 

// User can also specify caching expire
$ git config --global credential.helper 'cache --timeout 7200'
// After enabling credential caching, it will be cached for 7200 seconds (2 hours).