storagedriver/s3: Optimize s3 Delete test cleanup.
storagedriver/s3: Optimize s3 Delete test cleanup.

(cherry picked from commit e4af4dc3a6da6da724e7cff18cf5b6da6ef2a3fd)
Signed-off-by: Collin Shoop <9630196f04a576060ab1de02adc56567730c4ce8@digitalocean.com>

docker/distribution,thaJeztah/distribution,docker/distribution,thaJeztah/distribution