Remove Event.wrapper for Pocket related telemetry

[mcarare]

Breakout from #21292.

┆Issue is synchronized with this Jira Task

[sflorean]

Verified as fixed on OnePlus 9 Pro (Android 12).
Glean:

{"timestamp":358,"category": "pocket", "name": "home_recs_shown"},{"timestamp":3856,"category": "pocket", "name": "home_recs_category_clicked", "extra":{"new_state": "selected", "category_name": "quick-reads", "selected_total": "0"}},{"timestamp":3900,"category": "pocket", "name": "home_recs_shown"},{"timestamp":4598,"category": "pocket", "name": "home_recs_category_clicked", "extra":{"selected_total": "1", "new_state": "selected", "category_name": "health"}},{"timestamp":4637,"category": "pocket", "name": "home_recs_shown"},{"timestamp":5106,"category": "pocket", "name": "home_recs_category_clicked", "extra":{"category_name": "self-improvement", "selected_total": "2", "new_state": "selected"}},{"timestamp":5149,"category": "pocket", "name": "home_recs_shown"},{"timestamp":5601,"category": "pocket", "name": "home_recs_category_clicked", "extra":{"category_name": "science", "new_state": "selected", "selected_total": "3"}},{"timestamp":5632,"category": "pocket", "name": "home_recs_shown"}.