Handle new Container Scanning report format

What does this MR do?

This MR adds support for handling the new CS report format which uses the Security Products Common Format

The following changes have been made:

1. Deprecate current clair-scanner formatted gl-container-scanning-report.json fixture file
2. Add new gl-container-scanning-report.json fixture file formatted using Security Products Common Format
3. Add conditional to rails parser to check for the existence of an image field in the container scanning report file. If this field exists, we parse the deprecated clair-scanner formatted report, otherwise we don't parse the report since it's already in the new Security Products Common Format.

Closes #33825 (closed)

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team