CSAF / SSVC integration 2024

[ahouseholder]

Describe the solution you'd like

This issue is for tracking integration with CSAF and SSVC

See also

• OASIS CSAF issue: Include support for SSVC oasis-tcs/csaf#803
• https://groups.oasis-open.org/discussion/motion-for-803#bm87c96b9f-de9e-4b75-9a60-25f534cfbbda

[tschmidtb51]

@ahouseholder: Sorry for the late reply.
Unfortunately, #642 did not completely change the schema base. Here is the issues that I see so far:

• definitions is not longer valid. It needs to be changed to $defs => PR available in SSVC JSON Schema 2020-12 #654