Improve csaf ingestion by caching existing purl statuses

[dejanb]

Currently we have a query in the loop while ingesting csaf documents

trustify/modules/ingestor/src/service/advisory/csaf/creator.rs

Line 246 in 88c8632

let package_status = purl_status::Entity::find()

This query will check if the status already exists before preparing the new one for ingestion. This can be expensive for documents with large number of statuses. The better approach would be to get all statuses based on advisory and vulnerability once before the loop and the check if purl/status combo already exists in the cache.