- Fixed a long-standing bug where the :class:`.Enum` type as used

- Fixed a long-standing bug where the :class:`.Enum` type as used
with the psycopg2 dialect in conjunction with non-ascii values
and ``native_enum=False`` would fail to decode return results properly.
This stemmed from when the PG :class:`.postgresql.ENUM` type used
to be a standalone type without a "non native" option.
fixes #3354
- corrected the assertsql comparison rule to expect a non-ascii
SQL string