collect: skip if cache dir doesn't exist
collect: skip if cache dir doesn't exist

Related to #872

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

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