Pictures within tables not in the specified 2-column format in generated PDF files

[ribose-jeffreylau]

Problem description

As titled.

Each picture would individually take up a whole page in the generated PDF.

They are fine in the generated HTML though.

For example, sources/csd-report-conference-42.adoc

[cols="a,a"]
|===

|image::img_0409-43.jpg[]
|image::img_0415-51.jpg[]
|image::img_0498-45.jpg[]
|image::img_0504-49.jpg[]
|image::img_0590-53.jpg[]
|image::img_0608-55.jpg[]

|===

cc: @wsdwl