Support specifying a kubeconfig

[DaruZero]

Is this a request for help?: No

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Is this a BUG REPORT or FEATURE REQUEST? (choose one): Feature request

It would be great to be able to specify a kubeconfig file to use instead of relying only on the default ~/.kube/config. I've tried to workaround this by passing the --helm-extra-args "--kubeconfig $KUBECONFIG_FILE" flag, but the problem is that the extra arg does not (rightfully) get passed to the kubectl commands used to check the installation. So in my case, where I don't even have the ~/.kube/config file but just a runtime-generated kubeconfig file, the trick does not work, as the chart would get correctly installed but the check fails regardless
Another side effect of that workaround is that if there actually is a ~/.kube/config with a current context set to a different cluster than the given one, the kubectl check could pass even if the chart didn't install correctly

I would be willing to work on implementing this feature if necessary. I'd say that an optional --kubeconfig flag available for the install command would be beneficial, and should not have bad implications.

Let me know what you think