The old aws unit test is not very useful now, because there's the new
integration test which covers a lot more. Therefore, this commit
removes it.
Fixes#512
us-east-1 seems to very slow these days, some imports can take up to
15 minutes. This commit raises the number of attempts before we give up.
Previously, we did 40 attempts, each delayed by 15 seconds, making the total
timeout equal to 10 minutes. Now we do 80 attempts with the same delay,
making the total timeout 20 minutes.
After the snapshot is imported to EC2, there's no point in having the s3
object anymore. If the s3 object is not deleted, the user will be charged
for it periodically, while the object doesn't provide any value.
