* Revert "Define a better monthly pageview usage (#3564)"

This reverts commit 57188a402aa3917ddb2dab47d8adaae3077e0cb3.

* Extract migration from https://github.com/plausible/analytics/blob/57188a402aa3917ddb2dab47d8adaae3077e0cb3/priv/repo/migrations/20231129103158_add_allow_next_upgrade_override_to_users.exs