Remove labels from service objects in TestDotnet_Guestbook (#3500)

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### Proposed changes

Test failures identified in #3480 surfaced a regression in upstream
pulumi/pulumi. The usage of the deployment's labels as the service
object's label is unnecessary, since it is empty and can be removed.
This PR removes them to unblock CI.

### Related issues (optional)

Closes: #3480

tests/sdk/dotnet/guestbook/Program.cs

@@ -73,10 +73,6 @@ static Task<int> Main(string[] args)
 
             var redisMasterService = new Pulumi.Kubernetes.Core.V1.Service("redis-master", new ServiceArgs
             {
-                Metadata = new ObjectMetaArgs
-                {
-                    Labels = redisMasterDeployment.Metadata.Apply(metadata => metadata.Labels),
-                },
                 Spec = new ServiceSpecArgs
                 {
                     Ports =
@@ -152,10 +148,6 @@ static Task<int> Main(string[] args)
 
             var redisReplicaService = new Pulumi.Kubernetes.Core.V1.Service("redis-replica", new ServiceArgs
             {
-                Metadata = new ObjectMetaArgs
-                {
-                    Labels = redisReplicaDeployment.Metadata.Apply(metadata => metadata.Labels),
-                },
                 Spec = new ServiceSpecArgs
                 {
                     Ports =
@@ -231,10 +223,6 @@ static Task<int> Main(string[] args)
 
             var frontendService = new Pulumi.Kubernetes.Core.V1.Service("frontend", new ServiceArgs
             {
-                Metadata = new ObjectMetaArgs
-                {
-                    Labels = frontendDeployment.Metadata.Apply(metadata => metadata.Labels),
-                },
                 Spec = new ServiceSpecArgs
                 {
                     Type = isMiniKube ? "ClusterIP" : "LoadBalancer",