aws: don't forget to finish_target() after sync is done
aws: don't forget to finish_target() after sync is done

Fixes #101

Signed-off-by: Ruslan Kuprieiev <f6538312ce47017d734b1357aabc970ebf896e32@gmail.com>

dmpetrov/dataversioncontrol,ophiry/dvc,efiop/dvc,dmpetrov/dataversioncontrol,dataversioncontrol/dvc,dataversioncontrol/dvc,efiop/dvc,ophiry/dvc