setup environment for integration tests execution

[andrei-panov]

It would beneficial to setup an environment that we can use for integration tests when we call for the subcommands like kubectl and others. As the first step, I would offer do not to concentrate on the output of the executed subcommands but mainly on validating the strings which we pass down. Exit code and might be very broad check for some Headers in the output or something.

The goal here not to check if certain subcommands work but check if a certain cli-interface provided by kubectl... still matches the combination of strings which we pass.

Currently, we have very simple calls like kubectl get ns and others like "aliyun configure set --access-key-id="+string(accessKeyID[:])+" --access-key-secret="+string(accessKeySecret[:])+" --region="+region.

In total, we have about 60 subcommands calls, and the question is if can prove that all of them still valid? The same question will arise once used subcommands will release their new versions.