fix unused linter error

Can be seen for example in: https://github.com/knative/eventing/actions/runs/21171606060/job/60889521311

```
  Error: pkg/requestreply/ingress_handler.go:352:6: func isResponseEvent is unused (unused)
  func isResponseEvent(event *cloudevents.Event, rr *v1alpha1.RequestReply) bool {
       ^
  Error: test/conformance/helpers/tracing_test_helper.go:53:3: const recordEventsPodName is unused (unused)
  		recordEventsPodName = "recordevents"
  		^
  Error: test/conformance/helpers/tracing_test_helper.go:98:6: func getTraceIDHeader is unused (unused)
  func getTraceIDHeader(t *testing.T, evInfos []recordevents.EventInfo) string {
       ^
  3 issues:
  * unused: 3
```

Author: simkam

pkg/requestreply/ingress_handler.go

@@ -348,8 +348,3 @@ func (h *IngressHandler) handleReplyEvent(responseWriter http.ResponseWriter, ev
 	// send the reply event back to the original response writer
 	pr.replyEvent <- event
 }
-
-func isResponseEvent(event *cloudevents.Event, rr *v1alpha1.RequestReply) bool {
-	_, ok := event.Extensions()[rr.Spec.ReplyAttribute]
-	return ok
-}

test/conformance/helpers/tracing_test_helper.go

@@ -21,13 +21,9 @@ import (
 	"testing"
 
 	cetest "github.com/cloudevents/sdk-go/v2/test"
-	"go.opentelemetry.io/otel/propagation"
-	"go.opentelemetry.io/otel/trace"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-
 	tracinghelper "knative.dev/eventing/test/conformance/helpers/tracing"
 	testlib "knative.dev/eventing/test/lib"
-	"knative.dev/eventing/test/lib/recordevents"
 )
 
 // SetupTracingTestInfrastructureFunc sets up the infrastructure for running tracing tests. It returns the
@@ -49,14 +45,14 @@ func tracingTest(
 	setupInfrastructure SetupTracingTestInfrastructureFunc,
 	channel metav1.TypeMeta,
 ) {
-	const (
-		recordEventsPodName = "recordevents"
-	)
-
 	client := testlib.Setup(t, true, setupClient)
 	defer testlib.TearDown(client)
 
 	// TODO - redo with OTel
+	// const (
+	//     recordEventsPodName = "recordevents"
+	// )
+	//
 	// Start the event info store. Note this is done _before_ we setup the infrastructure, which
 	// sends the event.
 	// targetTracker, err := recordevents.NewEventInfoStore(client, recordEventsPodName, client.Namespace)
@@ -95,15 +91,15 @@ func tracingTest(
 // getTraceIDHeader gets the TraceID from the passed in events.  It returns the header from the
 // first matching event, but registers a fatal error if more than one traceid header is seen
 // in that message.
-func getTraceIDHeader(t *testing.T, evInfos []recordevents.EventInfo) string {
-	for i := range evInfos {
-		if nil != evInfos[i].HTTPHeaders {
-			sc := trace.SpanContextFromContext(propagation.TraceContext{}.Extract(context.TODO(), propagation.HeaderCarrier(evInfos[i].HTTPHeaders)))
-			if sc.HasTraceID() {
-				return sc.TraceID().String()
-			}
-		}
-	}
-	t.Fatalf("FAIL: No traceid in %d messages: (%v)", len(evInfos), evInfos)
-	return ""
-}
+// func getTraceIDHeader(t *testing.T, evInfos []recordevents.EventInfo) string {
+// 	for i := range evInfos {
+// 		if nil != evInfos[i].HTTPHeaders {
+// 			sc := trace.SpanContextFromContext(propagation.TraceContext{}.Extract(context.TODO(), propagation.HeaderCarrier(evInfos[i].HTTPHeaders)))
+// 			if sc.HasTraceID() {
+// 				return sc.TraceID().String()
+// 			}
+// 		}
+// 	}
+// 	t.Fatalf("FAIL: No traceid in %d messages: (%v)", len(evInfos), evInfos)
+// 	return ""
+// }