Kind represents the kinds of notes supported.

VULNERABILITY The note and occurrence represent a package vulnerability.
BUILD The note and occurrence assert build provenance.
IMAGE This represents an image basis relationship.
PACKAGE This represents a package installed via a package manager.
DEPLOYMENT The note and occurrence track deployment events.
DISCOVERY The note and occurrence track the initial discovery status of a resource.
ATTESTATION This represents a logical "role" that can attest to artifacts.
UPGRADE This represents an available package upgrade.