Validate CycloneDX PURLs

[DennisClark]

Validation of PURLs in the CycloneDX SBOM

Deliverable: Validate that correct PURLs are used to consistently identify packages in the SBOM

Reuse/update/test the "Validate PURL" library.

[mallurivikas]

Hi @DennisClark @pombredanne I’ve been going through the PURL specification and the CycloneDX SBOM format to understand the validation flow. This issue looks clear and well-scoped may I take this up and try to work on it?