We were using the same logic in four different places, so we're creating
a new class to handle that logic.
Note that I didn't find a way to delegate the `content` method to a
`Admin::TableActionsComponent`, so we're delegating the `action` method
instead. That means we need to create a method returning an
`Admin::TableActionsComponent`. We also need to cache this object;
otherwise we were getting an error when calling `actions.action` from
the `Admin::Poll::Questions::TableActionsComponent`.
