Revert "Revert "Enable the swift logs env vars for all jobs""

Now that zuul_swift_upload.py should be working with centos
turn the log instructions back on.

This reverts commit a764666e083d976410acb97b6ce91bd9b3b07c2a.

Change-Id: Id2cfbde3a483441e090f1888bc6f5d5eafc30d24
Merge "Revert "Revert "Enable the swift logs env vars for all jobs"""