Chrome shows security warning when in an Agile board view

Issue Summary

When accessing either a Kanban bard view, or a Scrum board view, Chrome shows a security warning:

That's not being caused by an actual effective security breach, but because that page is loading an image from a non HTTPS domain:

Steps to Reproduce

Access a kanban or scrum board of a JSW project.

Expected Results

No security warning messages should be displayed, the site should still be marked as secure.

Actual Results

A security warning is displayed.

Workaround

We can't avoid that until that resource is removed/modified. So there is no workaround at the moment.