Moving an assigned task to a route does not move the linked task IN THE WEB DISPATCH INTERFACE

[Paul-Eraman-CoopCycle]

Describe the bug title

To Reproduce Steps to reproduce the behavior: have an assigned task with a linked task drag and drop one task to a route the task moves to the route and the route moves to the messenger but dosnt assign the linked task

Expected behavior the route should remain unassigned and the taska nd its linked task should move to the route

Screenshots DM video

[Atala]

Linked to coopcycle/coopcycle-app#1713