Cannot translate messages in network_qos edit-rule form

There are strings which cannot be translated in network_qos edit-rule form.

It is because strings passed to gettext() contains variables. Such variables are evaluated as empty when generating the POT file. For example, a string in [1] will be "Bandwidth Limit - , , , " in the djangojs POT file.

On the other hand, when displaying the form these variables are evaluated and the corresponding string in PO file cannot be found.

edit-rule.controller.js contains the similar strings as [1].

When we need to pass variables to a translatable string, we should use interpolate() as we do in many files.

[1] https://opendev.org/openstack/horizon/src/branch/master/openstack_dashboard/static/app/core/network_qos/actions/edit-rule.controller.js#L42-L43