MySQL introspector returns columns in non-deterministic order
When I use the introspector to generate model classes for MySQL tables, the order of columns seems non-deterministic. It turns out that `MySQLDatabase.get_columns()` does not fetch columns ordered by their ordinal position. (Sometimes the columns are simply returned alphabetically, from what I observed.) Could we add `ORDER BY ordinal_position` when selecting from the `information_schema.columns` table in MySQL?

Here is the code for MySQL, and there is no `ORDER BY` clause:
https://github.com/coleifer/peewee/blob/e4f5df28e1b3716de1c006652371744da3743018/peewee.py#L4193-L4197

We can see that for PostgreSQL, columns are returned in a deterministic order:
https://github.com/coleifer/peewee/blob/e4f5df28e1b3716de1c006652371744da3743018/peewee.py#L3983-L3988