Firewall groups explicit ordering #6471

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Is your feature request related to a problem? Please describe.

I would like to be able to set the internal priority between firewall groups in an explicit way, so that when an interface is a member of more than one group, the rules are applied in an order not determined by the name of the groups, but by their given priority.

Right now the priority between firewall groups seems to be based on the ascending alphabetical ordering between group names.

Describe the solution you like

In the "Firewall: Groups" page, I would like to be able to reorder groups. Possible solutions could be drag-and-drop or arrows to move groups up and down, or maybe a "Move selected groups after this group"-button, that would be more in line with the firewall rules page. The groups should (still) be listed in their applied order, and this should also be communicated on the page.

Describe alternatives you considered

N/A

Additional context

The experienced alphabetical ordering is also backed by this forum post.