Line block not correctly parsed

[acolombier]

Hi,

I was unable to get Line Block to work correctly. Here is a minimal example

.. flat-table:: Test

* - Link
  - Button
  - | Baz
    | Foo
    | Bar

Instead of rendering a table like so

Link	Button	Baz Foo Bar

It render this

Link	Button	|Baz|Foo|Bar

I have managed to fix this by changing this line to:

for elem in list(cellItem.findall(lambda n: isinstance(n, (colSpan, rowSpan)))):

Not sure if there is a better fix?