[Bug] Editing multiple Epic labels removes all existing labels

Summary

V13.10.0

When editing multiple epics and applying a new label, upon pressing 'update all' it will remove any labels that those epics have except the new label. This does not happen when updating single epics in this way (the epic will keep its other labels)

Steps to reproduce

Go to group epic list. Click edit epics, click multiple epics and click a new label to apply, click update all.

What is the current bug behavior?

Existing epic labels removed.

What is the expected correct behavior?

Existing (non-scoped) epic labels persist.