Updated query known and slsa parser

[Yaxhveer]

Description of the PR

Fixes #2016 Fixes #2015

Updated known command for hasSBOM to check for packages with attached artifacts having sboms. Updated getSlsaEntity to use subjects uri as PURL.

PR Checklist

• [x] All commits have a Developer Certificate of Origin (DCO) -- they are generated using -s flag to git commit.
• [x] All new changes are covered by tests
• [ ] If GraphQL schema is changed, make generate has been run
• [ ] If GraphQL schema is changed, GraphQL client updates/additions have been made
• [ ] If OpenAPI spec is changed, make generate has been run
• [ ] If ent schema is changed, make generate has been run
• [ ] If collectsub protobuf has been changed, make proto has been run
• [ ] All CI checks are passing (tests and formatting)
• [ ] All dependent PRs have already been merged