Make sure to set the namespace in config

Or the SA will try to match every ConfigMap on cluster when we only want
to scope to the running configmap in namespace

pkg/adapter/adapter.go

@@ -26,6 +26,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"knative.dev/eventing/pkg/adapter/v2"
 	"knative.dev/pkg/logging"
+	"knative.dev/pkg/system"
 )
 
 const globalAdapterPort = "8080"
@@ -40,7 +41,11 @@ type envConfig struct {
 }
 
 func NewEnvConfig() adapter.EnvConfigAccessor {
-	return &envConfig{}
+	return &envConfig{
+		adapter.EnvConfig{
+			Namespace: system.Namespace(),
+		},
+	}
 }
 
 type listener struct {