Migrate tests from "model/cluster_stats_test.go" to use testify (#12580)

model/cluster_stats_test.go

@@ -6,6 +6,8 @@ package model
 import (
 	"strings"
 	"testing"
+
+	"github.com/stretchr/testify/require"
 )
 
 func TestClusterStatsJson(t *testing.T) {
@@ -13,7 +15,5 @@ func TestClusterStatsJson(t *testing.T) {
 	json := cluster.ToJson()
 	result := ClusterStatsFromJson(strings.NewReader(json))
 
-	if cluster.Id != result.Id {
-		t.Fatal("Ids do not match")
-	}
+	require.Equal(t, cluster.Id, result.Id, "Ids do not match")
 }