fix: filter out comment node to prevent sorting issue with collapsibl…

[Belinda-advmeds]

Issue When a table has collapsible items, or the table row has dynamic items depending on vue directive v-if/v-show, the dragging behavior is wired and the sorting order is wrong.

Root Cause In addition to the actual rows, the rows with v-if directive false will be comment nodes which causes the dragging target is wrong.

Solution Filter out comment nodes to avoid the bug