Set cataloger names within package cataloger task

[wagoodman]

ELF packages do not have the found-by field set:

❯ syft localhost/elf-test -o json | jq '.artifacts[] | select(.name == "alex")'
{
  "id": "a428c7d43ccc1e36",
  "name": "alex",
  "version": "v1.2.3",
  "type": "deb",
  "foundBy": "",
  ...
  "purl": "pkg:deb/[email protected]",
  "metadataType": "elf-binary-package-note-json-payload",
  "metadata": {
    "type": "deb"
  }
}

This PR fixes this behavior to always include the cataloger name.