add option to use kubectl with sudo

[Corwind]

It's useful when using user other than root to be able to use sudo to run kubectl, especially on operating systems that do not allow root login from ssh.

The default behavior does not change as the default value for the new variable is "false" and thus the default command to invoke kubectl does not change either.

[xunleii]

Hi @Corwind, sorry to respond lately.

Thanks for your contribution, I appreciate. This PR just need two things:

• Running tf fmt in order to keep the code clean (wrong identation)
• Ignoring the trigger kubectl_cmd on lifecycle because we don't want to recreate resources if we change this value.

[Corwind]

Hi @xunleii I'll look into it today or tomorrow depending on how busy I am today :)

[Corwind]

@xunleii I had a little time to work on it, I updated my version if you want to have a look at it. I added the kubectl_cmd trigger to be ignored on lifecyle and I ran terraform fmt.

[xunleii]

I'll check that this noon or after work. Thanks for your changes 😄

[xunleii]

LGTM