Fix kubeConfig redefined issue and update imagePullPolicy

[Jeffwan]

Pull Request Description

1. controller-manager failed to start due to redefined kubeconfig #157 describe the startup problem, controller-runtime already have kubeconfig defined.
2. Since we use nightly image at this moment, it failed to load the new changes. Let's use Always for short term for testing. Once it's reliable, let's change back to IfNotPresent

Related Issues

Resolves: #157

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