Add support for handling different engines/sources of Policy Reports

[Jonas-Beck]

Currently, the Backstage plugin exposes the EntityKyvernoPolicyReportsContent component that uses the Kyverno source to display Kyverno policies related to the specific Backstage component. We should create additional components for other sources like Trivy and Falco, allowing users to integrate these tools with their Backstage instance if they use them.

This would also make it easier to change the view based on the best way to present policies related to each source.

Additionally, it might make sense to make the component naming more consistent when adding more sources. Suggested naming conventions could be:

• EntityKyvernoPoliciesContent
• EntityTrivyPoliciesContent
• EntityFalcoPoliciesContent