batches: refetch batch change after performing bulk action

Created by: courier-new

Another small improvement for #24417 (closed).

I think this was the main reason for originally polling this query; when a user performs a bulk operation, we want to refetch the batch change details so that we have the updated active bulk operations handy to display the alert and update the count on the tab. Technically, we don't care about refetching all the other details of the batch change, but this is still a performance improvement over continuously polling every 5 seconds, and it's almost instant when the bulk operation begins, whereas before it might have taken up to 5 seconds to see that update.

Based on #25379 because it was easier.