Rename Vulnerabilities::Findings::CreateFromSecurityFindingService

As discussed here, we should find a more appropriate name for Vulnerabilities::Findings::CreateFromSecurityFindingService.

We may also want to consider if this process should be a Service or part of our /lib code.

This issue is a follow-up to the MR !88472 (merged) and it's related to issue #361948 (closed).