[WIP] Compose SCAP 1.3 DataStreams

[yuumasato]

This is a very early and rough patch to update openscap to compose SCAP 1.3 compliant Data Streams.

What this PR does for now:

• When a check-content-ref's href attribute is a supported URL (i.e.: http:// or https://)
  • Add a uri entry in the Benchmarks component-ref catalog, but don't include its contents in DS
  • Add a component-ref to datastream's <ds:checks>

What it needs to do:

• Get the path from the URL and generate the component name and uri.
• oscap_source_new_from_url not sure if makes sense to implement it.

Related to https://github.com/ComplianceAsCode/content/pull/4302

[jan-cerny]

I think we will need a test for this.

[evgenyz]

We are not using OpenSCAP to compose DS anymore. Closing.