Add container scanning for registry schema

What does this MR do?

Add container scanning for registry enum to scan.type to Container Scanning schema.

Then the new scan.type will be utilized to prevent components from being displayed on the security dashboard.

Note: I have updated the Container Scanning schema to allow scan.type to be 'container scanning for registry' instead of creating a new schema. This change will improve maintainability since both schemas are meant to be identical.

What are the relevant issue numbers?

gitlab-org/gitlab#443633 (closed)

Checklist

• Ensure changes can be built upon without requiring a breaking change, see Building for Extensibility.
• Review and add/update tests for this feature/bug.
• Add an entry to the CHANGELOG if required, with the appropriate version. See Classifying Changes.
• Assign the MR to the appropriate person/people for review.

Closes #443633