Bugzilla 1744245: Subscription should not point to deleted ip

Delete and recreate of a subscription object without any delay causes
operator install to fail.

How to reproduce:

1. Create a CatalogSource object, wait for it to become healthy.
2. Create a Subscription that refers to the CatalogSource above.
3. Wait for the operator to install successfully.
4. Update the CatalogSource
5. Wait for the updated CatalogSource to become healthy.
6. Delete the Subscription object ( created above ).
7. Recreate the Subscription object ( no time delay between delete
and create ). Delete and Create can be done one after another, there
is no need to make them concurrent.

Solution:
 - The InstallPlan object(s) are listed using a lister which may
   return a deleted InstallPlan object. Use a non-cached client
   to query list of InstallPlan object(s)

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1744245

Author: tkashem

pkg/controller/operators/catalog/operator.go

@@ -19,7 +19,6 @@ import (
 	extinf "k8s.io/apiextensions-apiserver/pkg/client/informers/externalversions"
 	k8serrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	utilclock "k8s.io/apimachinery/pkg/util/clock"
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
@@ -915,7 +914,7 @@ func (o *Operator) ensureInstallPlan(logger *logrus.Entry, namespace string, sub
 	}
 
 	// Check if any existing installplans are creating the same resources
-	installPlans, err := o.lister.OperatorsV1alpha1().InstallPlanLister().InstallPlans(namespace).List(labels.Everything())
+	installPlans, err := o.listInstallPlans(namespace)
 	if err != nil {
 		return nil, err
 	}
@@ -1563,6 +1562,20 @@ func (o *Operator) listSubscriptions(namespace string) (subs []*v1alpha1.Subscri
 	return
 }
 
+func (o *Operator) listInstallPlans(namespace string) (ips []*v1alpha1.InstallPlan, err error) {
+	list, err := o.client.OperatorsV1alpha1().InstallPlans(namespace).List(metav1.ListOptions{})
+	if err != nil {
+		return
+	}
+
+	ips = make([]*v1alpha1.InstallPlan, 0)
+	for i := range list.Items {
+		ips = append(ips, &list.Items[i])
+	}
+
+	return
+}
+
 // competingCRDOwnersExist returns true if there exists a CSV that owns at least one of the given CSVs owned CRDs (that's not the given CSV)
 func competingCRDOwnersExist(namespace string, csv *v1alpha1.ClusterServiceVersion, existingOwners map[string][]string) (bool, error) {
 	// Attempt to find a pre-existing owner in the namespace for any owned crd