Import tasks dialog styling

[henrychoy]

This fixes some styling issues on the import plugin tasks dialog in the edit plugin file page.

• When a row is expanded with the warning that existing params will be overwritten, the chips should line up vertically
• When a row is expanded with any warning, there should be a top and bottom border to help separate it from other rows
• When a row is expanded, clicking on the expanded part should select/deselect, and it should look like one big row.