Change snippet import logic from db

What does this MR do?

In this MR, when we import a project and we try to import the snippets, we need to replace the existing logic and reuse the existing one designed for snippet migrations. We need to do this because the existing code does not cover several existing edge cases that are fixed in the migration code.

Refs #219744 (closed)

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content