Postgres-cdc: postgres enum data type cannot ingest into RW as varchar

[StrikeW]

Describe the bug

postgres enum data type cannot ingest into RW as varchar

reported by a customer.

Error message/log

risingwave-standalone     | 2024-04-18T01:59:36.84041242Z ERROR   rw-streaming actor{otel.name="Actor 178" actor_id=178 prev_epoch=6302621750067200 curr_epoch=6302621815799808}:executor{otel.name="StreamCdcScan B200002715"}: risingwave_connector::parser::postgres: parse column failed column="source" error=error deserializing column 1: cannot convert between the Rust type `core::option::Option<alloc::string::String>` and the Postgres type `event_sources` suppressed_count=3

event_sources is a enum created by:

CREATE TYPE event_sources AS ENUM ('A', 'B', 'C', 'D', 'E');

To Reproduce

CREATE TABLE multiverse.source_priorities (
  id integer PRIMARY KEY,
  source varchar
) FROM db TABLE "public.source";

Expected behavior

No response

How did you deploy RisingWave?

No response

The version of RisingWave

No response

Additional context

No response