Add reportSnippet permission to snippet GraphQL

What does this MR do?

This MR adds the reportSnippet permission type to the snippet GraphQL endpoint.

Refs #36079 (closed)

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content