git pull --rebase. Unlike the other solution, you don't need to know the name of your destination branch.
If your upstream branch is not set, try git pull origin <branch> --rebase (credit to @Rick in the comments)
To set this option globally, use git config --global pull.rebase true (credit to @Artur Mustafin below)
# https://stackoverflow.com/questions/13106179/fatal-not-possible-to-fast-forward-aborting
//Answer taken from above link, please upvote his answer, if it works for you