Fixed eligible_resources to pass updated options when creating workflow

When placement_auto is true the workflow will not perform resource lookups
as a performance improvement for the UI.  When specifically requesting the
resources through the same methods the option needs to be forced to false.

https://bugzilla.redhat.com/show_bug.cgi?id=1123380
I would suggest an ```instance_double``` over a double, if you know what class you're expecting. If it's an ```MiqProvisionWorkflow``` then you'd use it like this:
```ruby
workflow = instance_double("MiqProvisionWorkflow", :allowed_hosts => [host])
```

Otherwise, substitute MiqProvisionWorkflow with the correct class.

:+1: for the ```active_record_instance_double``` though :smile: