Optimize relationships to licenses

[goneall]

In SPDX 3.0, we moved to having relationships for all the licenses.

In addition, a license can be a simple license expression or a fully parsed license.

To remove redundancy, we should try to re-use existing relationships and/or existing licenses.

Discussed on the implementers call on 16 Oct 2024

Suggestion on the call - we create a relationship between the simple license expression to the complex license relationship - we could then identify similar expressions.