Predicate status changes breaks prd predicates

[MicaiahReid]

Describe the bug
The recent changes made to the predicate status (#396, #397) have broken the loading of existing predicates from redis on restart. Because Chainhook tries to parse the existing predicates with old types to the new types, those predicates fail.

We'll need to write a migration script to update the existing predicates to the new types.

[MicaiahReid]

Migration completed! We've created this repo to be the home to future migration scripts for the chainhook redis db.