fix[offers] - remove force destroy of application offers

Removes force removal of application offers, but rather errors out if there are existing integrations
with the offer that must be removed first. This is a much cleaner way to destroy offers as the use
of the `force` flag may leave the Juju state with leftover artefacts.

internal/juju/offers.go

@@ -195,16 +195,17 @@ func (c offersClient) DestroyOffer(input *DestroyOfferInput) error {
 		return err
 	}
 
-	forceDestroy := false
-	//This code loops until it detects 0 connections in the offer or 3 minutes elapses
+	//This code loops until it detects 0 connections in the offer or 5 minutes elapses
 	if len(offer.Connections) > 0 {
 		end := time.Now().Add(5 * time.Minute)
 		for ok := true; ok; ok = len(offer.Connections) > 0 {
-			//if we have been failing to destroy offer for 5 minutes then force destroy
-			//TODO: investigate cleaner solution (acceptance tests fail even if timeout set to 20m)
+			//if we have been failing to destroy offer for 5 minutes then fail on destroy
 			if time.Now().After(end) {
-				forceDestroy = true
-				break
+				connections := make([]string, len(offer.Connections))
+				for i, connection := range offer.Connections {
+					connections[i] = fmt.Sprintf("%s:%s", connection.SourceModelUUID, connection.Endpoint)
+				}
+				return fmt.Errorf("offer %q has remaining integrations: %s", input.OfferURL, strings.Join(connections, ", "))
 			}
 			time.Sleep(10 * time.Second)
 			offer, err = client.ApplicationOffer(input.OfferURL)
@@ -214,7 +215,7 @@ func (c offersClient) DestroyOffer(input *DestroyOfferInput) error {
 		}
 	}
 
-	err = client.DestroyOffers(forceDestroy, input.OfferURL)
+	err = client.DestroyOffers(false, input.OfferURL)
 	if err != nil {
 		return err
 	}