Add e2e tests for the NodeLatencyMonitor feature

[antoninbas]

This is part of #5514.

The NodeLatencyMonitor feature is available (Alpha) in Antrea v2.1: #6120. However, we have no e2e tests for the feature yet.

Tests would need to cover the following:

• feature (latency probes) can be enabled / disabled by creating / deleting the default NodeLatencyMonitor CR
• ping interval can be changed by updating the default NodeLatencyMonitor CR
• latency information can be retrieved using the K8s API (v1alpha1.stats.antrea.io/NodeLatencyStats)

Ideally, the e2e tests would also validate that the feature can work on Windows Nodes (not officially supported yet).

[EraKin575]

I would like to work on this issue. Please assign me this issue

[antoninbas]

@EraKin575 You already expressed interest in working on a different issue earlier this week. Since you are first time contributor, I suggest that you focus on a single issue at a time.
I prefer not to assign issues to first-time contributors, as it's very easy to just express interest, but in practice what happens too often is that the person doesn't follow through. Then it creates confusion as other potential contributors think the issue is already being worked on, so no one ends up working on the issue for a while and it creates unnecessary delays. If you open a PR showing that you are actively working on the issue (even if the PR is incomplete), then I will assign the issue to you to make sure that there is no duplication of effort.

[Rupam-It]

Hi @antoninbas , @tnqn is this issue still on? If yes then, I can work on this.