Surprising ordering of native MySQL enums

[Expurple]

I discovered this while working on #2014. I'll quote my code comment from there:

    // Native enum comparisons are not portable.
    //
    // Postgres enums are compared by their definition order
    // (see https://www.postgresql.org/docs/current/datatype-enum.html#DATATYPE-ENUM-ORDERING).
    // Tea was defined as ('EverydayTea', 'BreakfastTea'), so EverydayTea is considered "smaller" than BreakfastTea.
    //
    // SQLite doesn't support enum types and SeaORM works around this limitation by storing them as strings.
    // When treated as strings, EverydayTea is not "smaller" than BreakfastTea!
    //
    // MySQL should be the same as Postgres (see https://dev.mysql.com/doc/refman/8.0/en/enum.html#enum-sorting),
    // but in practice this test case behaves like SQLite. I'm not sure why.

This should probably be investigated, although I'm not interested in doing that myself