Yml validation cleanups

[pyth0n1c]

A few issues resolved in this:

1. Baselines do not have filters. If we want/need filter macros for baselines, then we can either create them by hand or emit them with contentctl.
2. A number of search did NOT include Splunk Cloud as one of their products. I assume this omission was an error. Is that correct? Is there ever a reason that ESCU will NOT support all of the following?
   products:

• Splunk Enterprise
• Splunk Enterprise Security
• Splunk Cloud

[nasbench]

LGTM but you need to bump the versions before I approve.

And all ESCU content should support the 3 products, so it was an omission.