Add personal and project snippet monthly counters to usage data

What does this MR do?

After adding the new section for monthly counters in !34363 (merged), we have to add those for personal and project snippets.

In this MR we just add those.

Refs #219399 (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