Remove `cyclonedx_sbom_ingestion` feature flag

What does this MR do and why?

Describe in detail what your merge request does and why.

Removes the cyclonedx_sbom_ingestion feature flag. This feature has been globally enabled in production since January 3rd and performance has been stable. Sbom::IngestReportsWorker has a 99.98% job success rate.

FF rollout issue: #367711 (closed)

Dashbaord: https://log.gprd.gitlab.net/goto/cec9b990-8b98-11ed-85ed-e7557b0a598c

JSONSchemer::InvalidFileURI has been fixed with !108468 (merged).

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