Setting dbType to enum is not totally correct

[SOHELAHMED7]

Resolve below TODO:

File: src/lib/migrations/MysqlMigrationBuilder.php

L33

protected function buildColumnChanges(ColumnSchema $current, ColumnSchema $desired, array $changed):void
    {
        $newColumn = clone $current;
        foreach ($changed as $attr) {
            $newColumn->$attr = $desired->$attr;
        }
        if (static::isEnum($newColumn)) {
            $newColumn->dbType = 'enum'; // TODO this is concretely not correct
        }

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Part of #10

and

Part of cebe#180