Ingest SBOM reachability (issue 480627)

What does this MR do and why?

This MR stores the new reachability property from the CycloneDX report into the new reachability column in the sbom_occurrences table.
An example sbom component with unknown reachability:

{
    Name: "acorn",
    Version: "4.0.4",
    PURL: "pkg:npm/acorn@4.0.4",
    ComponentType: "library",
    BomRef: "pkg:npm/acorn@4.0.4",
    Properties: []cyclonedx.Property{
        {
            Name: "gitlab:dependency_scanning_component:reachability",
            Value: "unknown"
        },
    },
}

An example sbom component with in_use reachability: \

{
    Name: "acorn",
    Version: "4.0.4",
    PURL: "pkg:npm/acorn@4.0.4",
    ComponentType: "library",
    BomRef: "pkg:npm/acorn@4.0.4",
    Properties: []cyclonedx.Property{
        {
            Name: "gitlab:dependency_scanning_component:reachability",
            Value: "in_use"
        },
    },
}

The relevant issue is: #480627 (closed)
This MR Cannot be merged until this migration is merged and verified: !161746 (merged)

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