ref(models): Delete CodeReviewEvent table [2/3]

[vaind]

Drop the sentry_code_review_event table. This is the second step of the safe deletion process.

Stacked on #109420 (pending delete). Retarget to master after PR 1 merges.

This is PR 2 of 3:

1. ref(models): Pending-delete CodeReviewEvent table [1/3] #109420 — SafeDeleteModel with MOVE_TO_PENDING (removes model from Django state)
2. This PR — SafeDeleteModel with DELETE (drops the table)
3. Recreate the model with updated schema

[github-actions]

This PR has a migration; here is the generated SQL for src/sentry/migrations/1034_remove_code_review_event.py src/sentry/migrations/1035_delete_code_review_event.py

for 1034_remove_code_review_event in sentry

--
-- Moved model CodeReviewEvent to pending deletion state
--
-- (no-op)

for 1035_delete_code_review_event in sentry

--
-- Delete model CodeReviewEvent
--
DROP TABLE "sentry_code_review_event" CASCADE;