Detele the ‘ghost’ branch reference to prevent wrong git tab-completion

If you deleted a branch, even on all the remotes, but your git tab-completion still gives you the ghost branch, try to delete that branch reference by yourself, it may be in .git/packed-refs and .git/info/refs, in these two files, each reference will use one line, just delete the ghost branch here and git tab-completion will be good again!