[BC-36908] CVSS v4 mappings support

[ram-bugcrowd]

Description

• Adds support for using the CVSS v4 mapping from the Vulnerability Rating Taxonomy so that when CVSS version 4.0 is requested, the system uses cvss_v4 mapping data (full CVSS v4 vector strings) instead of always using cvss_v3.

Checklist:

• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I have added entries to CHANGELOG.md and marked it Added/Changed/Removed
• I have not incremented version.rb

PR in draft