Move dialog onConfirm handlers into modals that concern them

[rikimaru0345]

We have lots of modals that deal with (for example) deletion of resources.
These modals take an onConfirm handler, that deals with the aftermath (refreshing the resource list, showing toasts etc).

It doesn't really make sense that those would be in an extra callback, they can be inlined to the modal,
as the modals themselves are already specialized to the resource that is being modified/deleted.

That would reduce the amount of code whenever a modal is used, and prevent code duplication (the handling is the same, no matter where the call comes from anyway).