Database table for language trends over time

What does this MR do?

Database table for language trends over time.

• Introduce new DB table for tracking language trend over time.
• Feature is EE only thus the model is in the EE counterpart: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/16491

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry for user-facing changes, or community contribution. Check the link for other scenarios.
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content