Manage milestones not accessible from menu when external issue tracker in configured

Summary

Manage milestones not accessible from menu when external issue tracker in configured. We use JIRA, so we are redirected to JIRA when clicking on Issues. In the MR menu, milestones is not visible any longer (was there in 8.x)

Solution

So if issues is disabled, merge requests will have the following sub items:

list
labels
milestones

if issues is not disabled it will not have any subnav