Incorrect Bech32 Prefix for script-based DReps

**OS**
Your OS: Unbuntu

**Versions**
The `db-sync` version (eg `cardano-db-sync --version`):
PostgreSQL version: [13.5.0.1](https://github.com/IntersectMBO/cardano-db-sync/releases/tag/13.5.0.1)

**Build/Install Method**
The method you use to build or install `cardano-db-sync`: binaries

**Run method**
The method you used to run `cardano-db-sync` (eg Nix/Docker/systemd/none):

**Additional context**

**Problem Report**

- `drep_hash` table view does not reflect different bech32 prefix for script-based DReps
- As per CIP-0005, script based DReps use the prefix of `drep_script` whereas key based DReps use just `drep` [here](https://github.com/cardano-foundation/CIPs/blob/master/CIP-0005/README.md?plain=1#L110)