Align tests for stored and virtual generated columns

Hi,

I noticed that the tests for virtual and stored generated columns
contain the following comment;

-- keep these tests aligned with generated_stored.sql (or generated_virtual.sql)

However, it seems that some additional tests for virtual generated columns
disrupted that alignment, as they were not added to generated_stored.sql.

I've attached a patch to restore the alignment.

In addition, I moved the test confirming that user-defined types are not allowed
in virtual generated columns to the generated_virtual.sql-specific section,
since this test is not necessary for stored generated columns.

Regards,
Yugo Nagata

--
Yugo Nagata <nagata(at)sraoss(dot)co(dot)jp>