kubernetes: Exec timeout does not kick users out on kubectl client 1.21

What happened:

Exec-ing onto a pod does not kick you out.

What you expected to happen:

To get kicked out of the pod after the container runtime specified time is reached.

How to reproduce it (as minimally and precisely as possible):

• configure your kubectl client to 1.21
• kubectl exec -it <any pod> -- sh
• wait however long your container runtime is set to and see that it doesn’t kick you out.

Anything else we need to know?:

Environment:

• Kubernetes version (use kubectl version):

$ k version
Client Version: version.Info{Major:"1", Minor:"21", GitVersion:"v1.21.1", GitCommit:"5e58841cce77d4bc13713ad2b91fa0d961e69192", GitTreeState:"clean", BuildDate:"2021-05-12T14:18:45Z", GoVersion:"go1.16.4", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"21", GitVersion:"v1.21.1+IKS", GitCommit:"04e16b9d6c7af21e462f7ac675c34b667cd6149e", GitTreeState:"clean", BuildDate:"2021-05-24T08:19:13Z", GoVersion:"go1.16.4", Compiler:"gc", Platform:"linux/amd64"}

• Cloud provider or hardware configuration:
• OS (e.g: cat /etc/os-release):
• Kernel (e.g. uname -a):
• Install tools:
• Network plugin and version (if this is a network-related bug):
• Others: We’re using containerd 1.5.2 and konnectivity 0.19

/sig cli