Using the `when` conditional on a `with_` loop gets evaluated on each
loop iteration and will not skip a task entirely. Use the `skip`
attribute to ignore errors in this scenario but only `skip` when
`enable_cinder_backend_nfs` is not enabled. If it is enabled the
`nfs_shares` file should be required and this task should fail if it
does not exist.
Co-authored-by: Andrew Widdersheim <amwiddersheim@gmail.com>
Change-Id: I6b997dd943efe7b16beb63899c1488fa5353d996
Closes-Bug: #1641183
7bb88390d8