data validator with full mode don't support enum type

[giant-panda666]

What did you do?

1. create table with enum column in upstream
2. create full mode migration task which using full mode validator

What did you expect to see?

syncing and validating without error.

What did you see instead?

new of errorRowsStatus is increasing, and select from {task}_validator_error_change shows that type of enum data from binlog is int, but type of enum data from downstream is string.

Versions of the cluster

DM version (run dmctl -V or dm-worker -V or dm-master -V):

v7.5.1

Upstream MySQL/MariaDB server version:

5.7

Downstream TiDB cluster version (execute SELECT tidb_version(); in a MySQL client):

v7.5.1

How did you deploy DM: tiup or manually?

tidb-operator

Other interesting information (system version, hardware config, etc):

>
>

current status of DM cluster (execute query-status <task-name> in dmctl)

(paste current status of DM cluster here)

[fubinzh]

/severity major