Allow custom actions inside Actions component

[dartcafe]

As a developer, I want to use custom actions inside the action slot to deduplicate code.

I.e. in polls we created a custom action for deletion of several items: https://github.com/nextcloud/polls/blob/master/src/js/components/Actions/ActionDelete.vue

Currently actions component must be registered and applied inside the custom component, wich prevents using it inside an actions menu.

[raimund-schluessler]

@dartcafe Can you check if this issue is still valid, please? I think it should work now.

[dartcafe]

As soon, as I have time. Sorry, busy atm.

[Antreesy]

Allowed with limitations

[ShGKme]

I'd say it is still actual because of limitations

[dartcafe]

Just checked with v9. Custom and reusable actions are still not possible.