fix: disable WatchListClient feature gate in installation tests

k8s.io/client-go v0.35.0 defaults the WatchListClient feature gate to
true. This causes reflectors to use watch-list semantics which require
bookmark events from the API server. The fake clientset doesn't send
bookmark events, causing informers to hang indefinitely on HasSynced().

Set KUBE_FEATURE_WatchListClient=false in an init() function in the
test suite to ensure it takes effect before any informer is created.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: pasanw

pkg/controller/installation/installation_controller_suite_test.go

@@ -15,6 +15,7 @@
 package installation
 
 import (
+	"os"
 	"testing"
 
 	"github.com/onsi/ginkgo/v2"
@@ -25,6 +26,14 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/log/zap"
 )
 
+func init() {
+	// Disable WatchListClient feature gate for fake clientset compatibility.
+	// k8s.io/client-go v0.35.0 defaults WatchListClient to true, which makes
+	// reflectors require bookmark events that the fake clientset doesn't send,
+	// causing informers to hang indefinitely on HasSynced().
+	os.Setenv("KUBE_FEATURE_WatchListClient", "false")
+}
+
 func TestInstallation(t *testing.T) {
 	logf.SetLogger(zap.New(zap.WriteTo(ginkgo.GinkgoWriter), zap.UseDevMode(true), zap.Level(uzap.NewAtomicLevelAt(uzap.DebugLevel))))
 	gomega.RegisterFailHandler(ginkgo.Fail)